Version July 2025
Antidepressants increased the risk compared with placebo of suicidal thinking and behavior (suicidality) in children, adolescents, and young adults in short-term studies of major depressive disorder (MDD) and other psychiatric disorders. Anyone considering the use of amitriptyline in a child, adolescent, or young adult must balance this risk with the clinical need. Short-term studies did not show an increase in the risk of suicidality with antidepressants compared with placebo in adults older than 24 years; there was a reduction in risk with antidepressants compared with placebo in adults 65 years and older. Depression and certain other psychiatric disorders are themselves associated with increases in the risk of suicide. Patients of all ages who are started on antidepressant therapy should be monitored appropriately and observed closely for clinical worsening, suicidality, or unusual changes in behavior. Families and caregivers should be advised of the need for close observation and communication with the prescriber. Amitriptyline is not approved for use in pediatric patients.
Chronic pain management: Limited data available: Children and Adolescents: Oral: Initial: 0.1 mg/kg at bedtime; may advance as tolerated over 2 to 3 weeks to 0.5 to 2 mg/kg at bedtime (Ref).
Cyclic vomiting syndrome, prophylaxis: Limited data available:
Note: Prophylaxis is recommended for patients experiencing frequent symptoms (eg, monthly) or severe symptoms (eg, requiring hospitalization, lasting >2 days, resulting in significant school/work absences) (Ref).
Children ≥5 years and Adolescents: Oral: Initial: 0.2 to 0.5 mg/kg/day once daily, administered at bedtime. If needed, may titrate every 1 to 2 weeks (eg, by 5 to 10 mg increments) to a usual dose of 1 to 1.5 mg/kg/day; doses of 2 mg/kg/day or higher have been described; however, should be used with caution with careful titration, ECG monitoring, and therapeutic monitoring; doses may be divided for tolerability (Ref). In adults, the mean effective dose is 75 to 100 mg/day (Ref).
Major depressive disorder (unipolar): Limited data available:
Note: Controlled clinical trials have not shown tricyclic antidepressants to be superior to placebo for the treatment of depression in children and adolescents. Although dosing is included in some manufacturer's labeling for ages ≥12 years, a selective serotonin reuptake inhibitor (SSRI) is recommended first line for treatment of depression in children and adolescents with/without psychotherapeutic interventions. Amitriptyline may be beneficial for patients in whom first- and/or second-line treatment options have failed or with comorbid conditions (eg, migraines, chronic pain) (Ref).
Children ≥12 years and Adolescents: Oral: Usual initial range: 20 to 30 mg/day at bedtime or in divided doses (eg, 10 mg 3 times daily); titrate slowly at weekly intervals; maximum daily dose: 200 mg/day; in general, lower doses are recommended compared to doses in adults (Ref).
Migraine, prophylaxis: Limited data available (Ref):
Note: Pediatric migraine efficacy trials have been observed to have a high placebo response; a meta-analysis has shown that 30% to 61% of subjects receiving placebo report decreased number of migraine attacks or decrease in headache days. Specific to amitriptyline therapy, there is insufficient evidence in pediatric subjects to demonstrate a 50% reduction in headache frequency, headache days, and migraine-related disability compared to placebo. When amitriptyline is combined with cognitive behavioral therapy (CBT), trials have shown a reduction in number of headache days and migraine-related disability compared with amitriptyline plus headache education (Ref).
Children ≥8 years and Adolescents: Oral: Initial: 0.25 mg/kg/day once daily at bedtime; increase dose by 0.25 mg/kg/day every 2 weeks to 1 mg/kg/day; maximum daily dose: 100 mg/day; combining amitriptyline with CBT may also be effective at reducing headache days and migraine-related disability (Ref).
Discontinuation of therapy: Depression: Consider planning antidepressant discontinuation for lower-stress times, recognizing non–illness-related factors could cause stress or anxiety and be misattributed to antidepressant discontinuation (Ref). Upon discontinuation of antidepressant therapy, gradually taper the dose to minimize the incidence of discontinuation syndromes (withdrawal) and allow for the detection of reemerging disease state symptoms (eg, relapse). Evidence supporting ideal taper rates after illness remission is limited. APA and NICE guidelines suggest tapering therapy over at least several weeks with consideration to the half-life of the antidepressant; antidepressants with a shorter half-life may need to be tapered more conservatively, avoiding abrupt discontinuation of the medication to prevent withdrawal effects. After long-term (years) antidepressant treatment, WFSBP guidelines recommend tapering over 4 to 6 months, with close monitoring during and for 6 months after discontinuation. If intolerable discontinuation symptoms occur following a dose reduction, consider resuming the previously prescribed dose and/or decrease dose at a more gradual rate (Ref).
Switching antidepressants: Evidence for ideal antidepressant switching strategies in pediatric patients is sparse; strategies described in pediatric guidelines include a conservative approach (tapering and discontinuing the antidepressant before adding the second) and cross-titration (gradually discontinuing the first antidepressant while at the same time gradually increasing the new antidepressant). While consensus does not exist regarding which approach to utilize, it is important to note that the conservative approach runs the risk for exacerbation of symptoms or discontinuation syndrome; cross-titration may avoid these risks but may increase the risk for the development of adverse effects or serotonin syndrome (Ref). Cross-titration (eg, over 1 to 4 weeks depending upon sensitivity to discontinuation symptoms and adverse effects) is standard for most switches but is contraindicated when switching to or from a monoamine oxidase inhibitor. While not as common of a strategy, a direct switch may be considered when switching to another agent in the same or similar class (eg, when switching between 2 SSRIs), when the antidepressant to be discontinued has been used for <1 week, or when the discontinuation is for adverse effects such as increased suicidal thoughts and behaviors or worsening depression or mania. When choosing the switch strategy, consider the risk of discontinuation symptoms, potential for drug interactions, other antidepressant properties (eg, half-life, adverse effects, pharmacodynamics), and the degree of symptom control desired (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Children ≥12 years and Adolescents: There are no dosage adjustments provided in manufacturer's labeling; however, renally eliminated; use with caution.
Children ≥12 years and Adolescents: There are no dosage adjustments provided in manufacturer's labeling; however, hepatically metabolized; use with caution.
(For additional information see "Amitriptyline: Drug information")
Chronic fatigue syndrome–related sleep disorders and pain (off-label use): Based on limited evidence; recommendations based on expert opinion: Oral: Initial: 10 mg once daily 1 hour before bedtime; may increase dose gradually based on response and tolerability in 10 mg increments up to 50 mg/day at bedtime for sleep disorders; for patients with pain, titrate up to 100 mg/day given once daily at bedtime or in divided doses (Ref).
Cyclic vomiting syndrome, moderate to severe, prevention (off-label use): Oral: Initial: 10 to 25 mg once daily at bedtime; may increase dose based on response and tolerability in increments of 10 to 25 mg at weekly intervals up to 100 mg/day (Ref). Typically requires a trial of 1 to 2 months at a therapeutic dose to adequately assess efficacy (Ref).
Fibromyalgia (off-label use): Oral: Initial: 10 mg once daily, 1 to 3 hours before bedtime; gradually increase dose based on response and tolerability in 5 to 10 mg increments at intervals of ≥2 weeks up to 75 mg/day (Ref). Note: Some experts suggest lower starting doses of 5 mg once daily in patients sensitive to side effects and that a maintenance dose range of 20 to 30 mg/day is often adequate (Ref).
Functional dyspepsia (alternative agent) (off-label use):
Note: May be used to augment or replace proton pump inhibitor therapy in partial and nonresponders who have been tested for H. pylori and treated if positive (Ref).
Oral: Initial: 10 to 25 mg once daily at bedtime; may increase dose based on response and tolerability in increments of 10 to 25 mg at ≥1-week intervals up to a maximum of 50 mg/day (Ref). Some experts suggest a lower maintenance dose range of 20 to 30 mg/day. Typically requires a trial of 8 to 12 weeks at a therapeutic dose to adequately assess efficacy. If effective, reassess at 6 months and consider tapering; may resume if dyspepsia recurs (Ref).
Headache, tension type (prevention) (off-label use): Oral: Initial: 10 to 25 mg once daily at bedtime; may increase dose based on response and tolerability in 10 to 25 mg increments at intervals of ≥1 week, up to a maximum of 125 mg/day (Ref). A lower starting dose of 10 to 12.5 mg once daily at bedtime and smaller titration increments of 10 to 12.5 mg/day at 2- to 3-week intervals may reduce adverse effects and enhance adherence according to some experts (Ref). May require up to 12 weeks of treatment at a therapeutic dose to adequately assess efficacy. Once effective, continue for at least 3 to 6 months before attempting gradual tapering (Ref).
Interstitial cystitis (bladder pain syndrome) (off-label use): Oral: Initial: 10 mg once daily at bedtime; based on response and tolerability, increase dose after 1 week to 25 mg once daily and then at weekly intervals in 25 mg increments to a target dose of 75 to 100 mg/day (Ref). A maximum dose of up to 75 mg/day as tolerated is suggested by some experts (Ref).
Irritable bowel syndrome–associated pain and global symptoms (alternative agent) (off-label use): Oral: Initial: 10 to 25 mg once daily at bedtime; may gradually increase dose based on response and tolerability to a recommended dose of 50 to 100 mg/day (Ref). Some experts recommend 3 to 4 weeks of therapy before increasing the dose (Ref).
Major depressive disorder (unipolar) (alternative agent): Oral: Initial: 25 to 50 mg/day as a single dose at bedtime or in divided doses; increase dose based on response and tolerability in 25 to 50 mg increments at intervals of ≥1 week up to a usual dose of 100 to 300 mg/day (Ref). Some experts suggest an initial dose of 25 mg/day at bedtime for most patients, although higher starting doses of 50 to 100 mg/day and more rapid titration (eg, every few days) may be considered in closely supervised (eg, hospitalized) settings; for patients sensitive to adverse effects, may initiate with 10 mg daily with gradual titration in steps of 10 mg/day every few days or longer (eg, at intervals ≥1 week) (Ref).
Manufacturer's labeling: Dosing in prescribing information may not reflect current clinical practice. Oral: Initial: 75 to 100 mg/day as a single dose at bedtime or in divided doses
Migraine, prevention (off-label use):
Note: An adequate trial for assessment of effect is considered to be at least 2 to 3 months at a therapeutic dose (Ref).
Oral: Initial: 10 to 25 mg once daily at bedtime; increase dose based on response and tolerability in 10 to 25 mg increments at intervals of ≥1 week up to 150 mg/day (Ref). Some experts suggest that a lower maintenance dose range of 10 to 100 mg once daily at bedtime is often adequate and better tolerated (Ref).
Myofascial pain syndrome and related causes of chronic pain including myofascial pelvic pain, nonradicular neck pain, temporomandibular disorders, and vulvodynia (alternative agent) (off-label use):
Note: May consider for patients with persistent symptoms despite multimodal care and treatment with first-line agents (Ref).
Oral: Initial: 10 to 25 mg once daily at bedtime; may increase based on response and tolerability in 10 to 25 mg increments at intervals ≥1 week to a usual dosage range of 25 to 75 mg/day (Ref). Maximum: 150 mg/day (Ref); due to tolerability concerns, some experts avoid or use caution with nortriptyline doses >50 mg/day (nortriptyline and amitriptyline are equipotent) (Ref). May require 6 to 12 weeks of therapy (including 2 weeks at maximum tolerated dose) to adequately assess efficacy (Ref).
Neuropathic pain, chronic (including diabetic neuropathy) (off-label use): Oral: Initial: 10 to 25 mg once daily at bedtime; may gradually increase dose based on response and tolerability in 10 to 25 mg increments at intervals ≥1 week up to a usual dosage range of 25 to 125 mg/day once daily at bedtime or in 2 divided doses (Ref). Maximum: 150 mg/day given once daily at bedtime or in 2 divided doses (Ref). In patients with diabetic neuropathy, some experts recommend a maximum dose of 100 mg/day (Ref). May require 6 to 12 weeks of therapy (including 2 weeks at maximum tolerated dose) to adequately assess efficacy (Ref).
Postherpetic neuralgia (off-label use): Oral: Initial: 10 to 25 mg once daily at bedtime; may gradually increase dose based on response and tolerability in 10 to 25 mg increments at intervals of ≥1 week up to 150 mg/day given once daily at bedtime or in 2 divided doses (Ref).
Sialorrhea (off-label use): Oral: Usual dose: 10 to 25 mg once daily at bedtime. If necessary, may gradually increase dose based on response and tolerability up to 100 mg/day (Ref).
Discontinuation of therapy: When discontinuing antidepressant treatment that has lasted for ≥4 weeks, gradually taper the dose (eg, over 2 to 4 weeks) to minimize withdrawal symptoms and detect reemerging symptoms (Ref). For brief treatment (eg, 2 or 3 weeks), may taper over 1 to 2 weeks; <2 weeks treatment generally does not warrant tapering (Ref). Reasons for a slower taper (eg, over 4 weeks) include prior history of antidepressant withdrawal symptoms or high doses of antidepressants (Ref). If intolerable withdrawal symptoms occur, resume the previously prescribed dose and/or decrease dose at a more gradual rate (Ref). Select patients (eg, those with a history of discontinuation syndrome) on long-term treatment (>6 months) may benefit from tapering over >3 months (Ref). Evidence supporting ideal taper rates is limited (Ref).
Switching antidepressants: Evidence for ideal antidepressant switching strategies is limited; strategies include cross-titration (gradually discontinuing the first antidepressant while at the same time gradually increasing the new antidepressant) and direct switch (abruptly discontinuing the first antidepressant and then starting the new antidepressant at an equivalent dose or lower dose and increasing it gradually). Cross-titration (eg, over 1 to 4 weeks depending upon sensitivity to discontinuation symptoms and adverse effects) is standard for most switches, but is contraindicated when switching to or from an MAOI. A direct switch may be an appropriate approach when switching to another agent in the same or similar class (eg, when switching between two SSRIs), when the antidepressant to be discontinued has been used for <1 week, or when the discontinuation is for adverse effects. When choosing the switch strategy, consider the risk of discontinuation symptoms, potential for drug interactions, other antidepressant properties (eg, half-life, adverse effects, and pharmacodynamics), and the degree of symptom control desired (Ref).
Switching to or from an MAOI:
Allow 14 days to elapse between discontinuing an MAOI and initiation of amitriptyline.
Allow 14 days to elapse between discontinuing amitriptyline and initiation of an MAOI.
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
The renal dosing recommendations are based upon the best available evidence and clinical expertise. Senior Editorial Team: Bruce Mueller, PharmD, FCCP, FASN, FNKF; Jason A. Roberts, PhD, BPharm (Hons), B App Sc, FSHP, FISAC; Michael Heung, MD, MS.
Altered kidney function: Mild to severe impairment: No dosage adjustment necessary (Ref); use with caution.
Hemodialysis, intermittent (thrice weekly): Unlikely to be dialyzed (large Vd): No supplemental dose or dosage adjustment necessary (Ref); however, dialysis patients have demonstrated increased sensitivity to the anticholinergic side effects of tricyclic antidepressants (TCAs) (potentially due to accumulation of glucuronide metabolites). Use with caution (or avoid use) along with close monitoring for both anticholinergic and QT prolonging effects (Ref).
Peritoneal dialysis: Unlikely to be dialyzed (large Vd): No dosage adjustment necessary (Ref); however, dialysis patients have demonstrated increased sensitivity to the anticholinergic side effects of TCAs (potentially due to accumulation of glucuronide metabolites). Use with caution (or avoid use) along with close monitoring for both anticholinergic and QT prolonging effects (Ref).
CRRT: Unlikely to be dialyzed: No dosage adjustment necessary (Ref).
PIRRT (eg, sustained, low-efficiency diafiltration): Unlikely to be dialyzed: No dosage adjustment necessary (Ref).
The hepatic dosing recommendations are based upon the best available evidence and clinical expertise. Senior Editorial Team: Matt Harris, PharmD, MHS, BCPS, FAST, FCCP; Jeong Park, PharmD, MS, BCTXP, FCCP, FAST; Arun Jesudian, MD, Sasan Sakiani, MD.
Note: Amitriptyline undergoes extensive first-pass metabolism in the liver to several active metabolites before being excreted in the urine. In patients with liver impairment, decreased hepatic metabolism leads to higher plasma concentrations, an increase in amitriptyline exposure, a longer half-life, and slower clearance of the active metabolites, including nortriptyline (Ref). Avoid use in patients who have encephalopathy with concomitant liver disease (Ref).
Liver impairment prior to treatment initiation:
Initial or dose titration in patients with preexisting liver cirrhosis:
Child-Turcotte-Pugh class A and B: Initial: Administer 50% of the usual recommended indication-specific dose; use with caution; may increase dose based on response and tolerability in small increments (eg, 5 to 12.5 mg increments) at intervals of ≥1 to 2 weeks, not to exceed the maximum recommended indication-specific dose or 100 mg/day, whichever is less (Ref).
Child-Turcotte-Pugh class C: Avoid use (Ref).
Liver impairment developing in patients already receiving amitriptyline:
Note: Dose adjustments should be done in collaboration with appropriate clinical expert (eg, psychiatry) (Ref).
Chronic disease progression (eg, outpatient):
Progression from baseline to Child-Turcotte-Pugh class A and B: Consider reducing dose by 50% or discontinuation of therapy, particularly if there are concerns for altered mentation; use with caution; do not exceed the maximum recommended indication specific dose or 100 mg/day, whichever is less (Ref).
Progression to Child-Turcotte-Pugh class C: Avoid use; switch to an alternative agent (Ref).
Acute worsening of liver function (eg, requiring hospitalization): Permanently discontinue therapy (without tapering) if amitriptyline-induced liver injury is suspected or confirmed (Ref).
Amitriptyline may cause anticholinergic effects, such as constipation (including fecal impaction), xerostomia, blurred vision, and urinary retention.
Mechanism: Binding affinity to the muscarinic receptor(s), permeability of the blood-brain barrier, and serum and tissue concentrations all influence the risk of anticholinergic effects (Ref). Amitriptyline is considered to have high anticholinergic activity at typical doses (Ref).
Risk factors:
• Older age (Ref)
• Higher doses (Ref)
• Concomitant use of drugs with anticholinergic properties (Ref)
• Specific tricyclic antidepressants: Amitriptyline has the highest degree of anticholinergic effects, while desipramine and nortriptyline have modest effects (Ref).
Amitriptyline may increase the risk of bleeding, particularly if used concomitantly with antiplatelets and/anticoagulants. Multiple observational studies with other drugs that interfere with serotonin reuptake (eg, selective serotonin reuptake inhibitors [SSRIs]) have found an association with use and a variety of bleeding complications. Similar to these agents, amitriptyline may increase the risk of bleeding (Ref).
Mechanism: Possibly via inhibition of serotonin-mediated platelet activation and subsequent platelet dysfunction. Amitriptyline is considered to display intermediate affinity for the serotonin reuptake receptor (Ref).
Onset: Varied; per SSRI-derived literature (ie, amitriptyline not included), bleeding risk is likely delayed for several weeks until SSRI-induced platelet serotonin depletion becomes clinically significant (Ref).
Risk factors:
• Concomitant use of antiplatelet agents and/or anticoagulants (based on SSRI-derived literature) (Ref)
• Preexisting platelet dysfunction or coagulation disorders (eg, von Willebrand factor) (Ref)
Amitriptyline may cause dose-dependent ECG changes (nonspecific), most commonly QRS prolongation (Ref), atrioventricular conduction disturbance, and cardiac arrhythmias, including sinus tachycardia. QT prolongation and ventricular arrhythmias may also occur. May precipitate heart block in patients with preexisting conduction system disease.
Mechanism: Inhibits cardiovascular sodium, calcium, and potassium channels (Ref). Sinus tachycardia is attributed to the inhibition of norepinephrine and anticholinergic action (Ref).
Risk factors:
• Increased age (Ref)
• Females (Ref)
• Presence of metabolic disease (Ref)
• Hypokalemia (Ref)
• Coadministration of drugs independently associated with QT interval prolongation or further increase risk of arrhythmia (amitriptyline shares electrophysiologic properties of type Ia antiarrhythmics such as quinidine, procainamide, and disopyramide) (Ref)
• Family history of congenital long QT syndrome (Ref). Note: Use is relatively contraindicated in patients with conduction abnormalities
Amitriptyline may cause dose-dependent CNS depression, including dizziness, drowsiness, a sedated state, ataxia, cognitive dysfunction, confusion, disorientation, and fatigue (Ref).
Mechanism: Dose related; alpha-adrenergic and histamine receptor blockade may cause dizziness (via orthostatic hypotension) and a high degree of sedation (Ref).
Onset: Varied; difficult to define; some symptoms may occur with first dose. A meta-analysis in inpatients treated with a tricyclic antidepressant (TCA), including amitriptyline, suggested that CNS toxicity (defined primarily as delirium or its prodromal symptoms) may have an insidious onset over 1 to 3 weeks following initiation or dose increase (Ref).
Risk factors:
• Concomitant alcohol
• Concomitant CNS depressants (eg, anticholinergics, antihistamines) (Ref)
• Females (Ref)
• Increased age (>55 years) (Ref)
• Increased TCA plasma levels, especially levels >300 ng/mL (Ref)
• Specific TCA: Amitriptyline has the highest risk of sedation among the TCAs (Ref)
Antidepressants (primarily selective serotonin reuptake inhibitors [SSRIs]) have been associated with an increased risk of bone fractures in observational studies (Ref). Tricyclic antidepressants, including amitriptyline, have also been associated with increased fracture risk (Ref).
Mechanism: Not fully elucidated; per SSRI-derived literature, may be related to a direct effect on bone metabolism via interaction with 5-HT and osteoblast, osteocyte, and/or osteoclast activity (Ref). Fall risk may be attributed to sedation, syncope, orthostatic hypotension, and/or confusion (Ref).
Onset: Varied; in a large, population-based case-controlled study, the increase risk of fracture with amitriptyline was more pronounced within the first 6 months of initiating therapy and declined with increasing duration of use (Ref).
Risk factors:
• Dose; amitriptyline is associated with fractures at low doses and a dose-dependent increase in risk has been observed (Ref)
• Concomitant use with other agents that may further affect physical balance and contribute to falls (eg, anxiolytics) (Ref).
Tricyclic antidepressants (TCAs) have been rarely associated with syndrome of inappropriate antidiuretic hormone secretion (SIADH) and/or hyponatremia, predominately in the elderly (Ref).
Mechanism: May cause SIADH via release of antidiuretic hormone (ADH) (Ref) or may cause nephrogenic SIADH by increasing the sensitivity of the kidney to ADH (Ref).
Onset: Varied; overall, hyponatremia risk is much higher within 2 to 4 weeks of initiating therapy and the risk seems to diminish over time. By 3 to 6 months, the hyponatremia risk is the same as for patients who do not take antidepressants (Ref).
Risk factors:
• Older age (Ref)
• Females (Ref)
• Concomitant use of diuretics (Ref)
• Low body weight (Ref)
• Lower baseline serum sodium concentration (Ref)
• Volume depletion (potential risk factor) (Ref)
• History of hyponatremia (potential risk factor) (Ref)
• Symptoms of psychosis (potential risk factor) (Ref)
• Specific antidepressant: TCAs have a lower risk for hyponatremia in comparison to selective serotonin reuptake inhibitors (SSRIs) (Ref)
Amitriptyline was implicated in contributing to 55% (61/110) of nonselective monoamine reuptake inhibitor-associated drug-induced liver injury cases reported between 2016 through 2021 (Ref). Case reports identify that amitriptyline-associated liver injury may manifest as increased serum transaminases (2% to 10%), prolonged cholestasis, or in rare cases, hepatic failure (Ref). Most cases of amitriptyline-associated liver injury resolve with therapy discontinuation but may take up to 2 years postexposure (Ref).
Mechanism: Immunologic; tricyclic antidepressant-induced hepatoxicity is associated with immune-mediated pathways (eg, eosinophilia, eosinophilic liver infiltration) (Ref).
Onset: Varied; amitriptyline-associated liver injury occurred between 1 to 8 months (Ref).
Risk factors:
• Prolonged exposure (Ref)
• Female birth gender (Ref)
• Coadministration of medications that are metabolized through the same CYP pathway (eg, diazepam) (Ref)
• Preexisting liver disease or increased risk for liver disease (Ref)
Amitriptyline is associated with acute angle-closure glaucoma (AACG) in a case report (Ref). May cause mild pupillary dilation, which, in susceptible individuals, can result in physical obstruction of the outflow of intraocular fluid. AACG may cause symptoms including eye pain, changes in vision, swelling, and redness, which can rapidly lead to permanent blindness if not treated (Ref).
Mechanism: May occur due to anticholinergic activity and mydriasis (Ref). May also be related to effects on serotonin or norepinephrine receptors in the iris and ciliary body of the eye (Ref).
Risk factors:
For AACG:
• Females (Ref)
• ≥50 years of age (slight increase) (Ref)
• Hyperopia (slight increase) (Ref)
• Personal or family history of AACG (Ref)
• Inuit or Asian descent (Ref)
Amitriptyline may cause orthostatic hypotension, which may lead to syncope and subsequent falls (Ref).
Mechanism: Alpha-adrenergic receptor blockade may lower systemic vascular resistance and result in hypotension, including orthostatic hypotension (Ref).
Onset: Varied; unclear; in a small study of elderly patients treated with amitriptyline 100 mg, orthostatic hypotension remained throughout the entire 5-week study period (Ref).
Risk factors:
• Cerebrovascular disease
• Cardiovascular disease
• Hypovolemia/dehydration (Ref)
• Concurrent medication use that may predispose to hypotension/bradycardia (Ref)
• Older adults, especially in those with preexisting heart conditions (Ref)
• Specific TCA: Amitriptyline is usually associated with a high risk for significant orthostatic hypotension (Ref)
Serotonin syndrome has been reported and typically occurs with coadministration of multiple serotonergic drugs (Ref). The diagnosis of serotonin syndrome is made based on the Hunter Serotonin Toxicity Criteria (Ref) and may result in a spectrum of symptoms, such as anxiety, agitation, confusion, delirium, hyperreflexia, muscle rigidity, myoclonus, tachycardia, tachypnea, and tremor. Severe cases may cause hyperthermia, significant autonomic instability (ie, rapid and severe changes in blood pressure and pulse), coma, and seizures (Ref).
Mechanism: Dose related; overstimulation of serotonin receptors by serotonergic agents (Ref).
Onset: Rapid; in the majority of cases (74%), onset occurred within 24 hours of treatment initiation, overdose, or change in dose (Ref).
Risk factors:
• Concurrent use of drugs that increase serotonin synthesis, block serotonin reuptake, and/or impair serotonin metabolism
Antidepressants are associated with an increased risk of suicidal thinking and suicidal behavior in pediatric and young adult patients (18 to 24 years) in short-term studies. In adults >24 years, short-term studies did not show an increased risk of suicidal thinking and behavior, and in older adults ≥65 years of age, a decreased risk was observed. Although data have yielded inconsistent results regarding the association of antidepressants and risk of suicide, particularly among adults, collective evidence shows a trend of an elevated risk of suicidality in younger age groups (Ref). Of note, the risk of a suicide attempt is inherent in major depression and may persist until remission occurs.
Mechanism: Not established; one of several postulated mechanisms is antidepressants may energize suicidal patients to act on impulses; another suggests that antidepressants may produce a worsening of depressive symptoms leading to the emergence of suicidal thoughts and actions (Ref).
Onset: Varied; increased risk observed in short-term studies (ie, <4 months) in pediatric and young adults; it is unknown whether this risk extends to long-term use (ie, >4 months).
Risk factors:
• Children and adolescents (Ref)
• Depression (risk of suicide is associated with major depression and may persist until remission occurs)
Withdrawal syndrome, consisting of both somatic symptoms (eg, dizziness, chills, light-headedness, vertigo, shock-like sensations, paresthesia, fatigue, headache, nausea, tremor, diarrhea, visual disturbances) and psychological symptoms (eg, anxiety, agitation, confusion, insomnia, irritability) has been reported, primarily following abrupt discontinuation of selective serotonin reuptake inhibitors (SSRIs). Withdrawal symptoms may also occur following gradual tapering (Ref).
Mechanism: Withdrawal; due to reduced availability of serotonin in the CNS with decreasing levels of the serotonergic agent. Other neurotransmission systems, including increased glutamine and dopamine, may also be affected, as well as the hypothalamic-pituitary-adrenal axis (Ref). May also be related in part to an adaptive hypersensitivity of muscarinic cholinergic receptors called cholinergic rebound or cholinergic overdrive (Ref).
Onset: Intermediate; based on data of withdrawal syndrome following SSRI discontinuation, expected onset is 1 to 10 days (following either abrupt or tapered discontinuation) (Ref).
Risk factors:
• Abrupt discontinuation (rather than dose taper) or tapering the antidepressant too quickly (Ref)
• Drugs with a half-life <24 hours (eg, paroxetine, venlafaxine) (Ref)
• Higher doses (Ref)
• Longer duration of treatment (eg, ≥4 weeks) (Ref)
• Prior history of antidepressant withdrawal symptoms (Ref)
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified. Anticholinergic effects may be pronounced; moderate to marked sedation can occur (tolerance to these effects usually occurs).
Frequency not defined:
Cardiovascular: Acute myocardial infarction, atrioventricular conduction disturbance, cardiac arrhythmia, cardiomyopathy (rare) (Ref), cerebrovascular accident, ECG changes (nonspecific) (Ref), edema, exacerbation of cardiac disease (Ref), facial edema, heart block, hypertension, orthostatic hypotension, palpitations, sinus tachycardia, syncope
Dermatologic: Allergic skin rash, alopecia, diaphoresis, skin photosensitivity, urticaria
Endocrine & metabolic: Altered serum glucose (inconclusive, but increased weight gain may increase insulin resistance) (Ref), decreased libido, galactorrhea not associated with childbirth, gynecomastia, increased libido, SIADH, weight gain, weight loss
Gastrointestinal: Ageusia, anorexia, constipation, melanoglossia, nausea, paralytic ileus, parotid gland enlargement, stomatitis, unpleasant taste, vomiting, xerostomia
Genitourinary: Breast hypertrophy, impotence, testicular swelling, urinary frequency, urinary retention, urinary tract dilation
Hematologic & oncologic: Eosinophilia, purpuric disease
Hypersensitivity: Tongue edema
Nervous system: Anxiety, ataxia, cognitive dysfunction, coma, confusion, delusion, disorientation, dizziness, drowsiness, dysarthria, EEG pattern changes, excitement, extrapyramidal reaction (including abnormal involuntary movements and tardive dyskinesia), fatigue, hallucination, headache, hyperpyrexia, insomnia, lack of concentration, nightmares, numbness, paresthesia, peripheral neuropathy, restlessness, sedated state, seizure, suicidal ideation, suicidal tendencies, tingling of extremities
Neuromuscular & skeletal: Asthenia, lupus-like syndrome, tremor
Ophthalmic: Accommodation disturbance, blurred vision, increased intraocular pressure, mydriasis
Otic: Tinnitus
Postmarketing:
Gastrointestinal: Cholestasis (Ref)
Hematologic & oncologic: Agranulocytosis (Ref), thrombocytopenia (Ref)
Hepatic: Hepatic failure (Ref), hepatitis (Ref), increased serum transaminases (Ref), jaundice (Ref)
Nervous system: Neuroleptic malignant syndrome (Ref), serotonin syndrome (Ref), withdrawal syndrome (Ref)
Ophthalmic: Angle-closure glaucoma (Ref)
Hypersensitivity to amitriptyline or any component of the formulation; coadministration with or within 14 days of MAOIs; coadministration with cisapride; acute recovery phase following myocardial infarction
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Canadian labeling: Additional contraindications (not in the US labeling): Severe liver impairment; acute heart failure
Disease-related concerns:
• Bariatric surgery: Presurgical assessment of the indication for use, symptoms, and goals of therapy should be documented to enable postsurgical assessment. A small pharmacokinetic study shows wide interpatient variability especially early post-surgery (eg, <30 days) (Wallerstedt 2021). Monitor for continued efficacy after bariatric surgery and consider switching to an alternate medication if symptoms worsen.
• Cardiovascular disease: Use with caution in patients with a history of cardiovascular disease (including previous MI, stroke, tachycardia, or conduction abnormalities).
• GI motility: Use with caution in patients with decreased GI motility (eg, paralytic ileus) as anticholinergic effects may exacerbate underlying condition.
• Hepatic impairment: Use with caution in patients with hepatic impairment; clearance is decreased, and plasma concentrations are increased. Due to the narrow therapeutic index, use lower initial and maintenance doses of tricyclic antidepressants. Avoid use in patients with hepatic encephalopathy due to the risk of neurocognitive effects (Mullish 2014).
• Mania/hypomania: May precipitate a shift to mania or hypomania in patients with bipolar disorder. Monotherapy in patients with bipolar disorder should be avoided. Combination therapy with an antidepressant and a mood stabilizer should also be avoided in acute mania or mixed episodes, as well as maintenance treatment in bipolar disorder due to the mood-destabilizing effects of antidepressants (CANMAT [Yatham 2018]; WFSBP [Grunze 2018]). Patients presenting with depressive symptoms should be screened for bipolar disorder. Amitriptyline is not FDA approved for the treatment of bipolar depression.
• Myasthenia gravis: Use with caution in patients with myasthenia gravis; may exacerbate condition (Mehrizi 2012).
• Ophthalmic conditions: Use with caution in patients with certain ophthalmic conditions (eg, increased intraocular pressure, narrow angle glaucoma, visual problems) as anticholinergic effects may exacerbate underlying condition.
• Renal impairment: Use with caution in patients with renal impairment.
• Seizure disorder: Use with caution in patients at risk of seizures, including those with a history of seizures, head trauma, brain damage, alcoholism, or concurrent therapy with medications which may lower seizure threshold.
• Urinary retention (eg, benign prostatic hyperplasia): Use with caution in patients with urinary retention as anticholinergic effects may exacerbate underlying condition.
Other warnings/precautions:
• Surgery: Recommended by the manufacturer to discontinue prior to elective surgery; risks exist for drug interactions with anesthesia and for cardiac arrhythmias. However, some experts recommend continuing tricyclic antidepressants prior to surgery (Pass 2004). Therapy should not be abruptly discontinued in patients receiving high doses for prolonged periods.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, Oral, as hydrochloride:
Generic: 10 mg, 25 mg, 50 mg, 75 mg, 100 mg, 150 mg
Yes
Tablets (Amitriptyline HCl Oral)
10 mg (per each): $0.18 - $0.32
25 mg (per each): $0.36 - $0.64
50 mg (per each): $0.71 - $1.27
75 mg (per each): $1.07 - $1.91
100 mg (per each): $1.43 - $2.54
150 mg (per each): $2.14 - $3.81
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, Oral, as hydrochloride:
Elavil: 10 mg, 25 mg, 50 mg, 75 mg
Generic: 10 mg, 25 mg, 50 mg, 75 mg, 100 mg
Oral: May administer with food to decrease GI upset.
Oral: Administer higher doses preferably at late afternoon or bedtime to minimize daytime sedation.
Store at 20°C to 25°C (68°F to 77°F). Protect from light.
An FDA-approved patient medication guide, which is available with the product information and at the following website, must be dispensed with this medication:
Antidepressant medications: https://www.fda.gov/downloads/drugs/drugsafety/ucm088660.pdf
Treatment of depression (FDA approved in adults); has also been used as adjunct therapy for chronic pain management, migraine prophylaxis, and prophylaxis of cyclic vomiting syndrome episodes. Note: Although manufacturer's labeling describes dosing in adolescents for depression, use has been replaced by other therapeutic classes with improved efficacy and adverse effect profiles (APA 2019; Cheung 2018; NICE 2019).
Amitriptyline may be confused with aminophylline, imipramine, nortriptyline
Elavil may be confused with Aldoril, Eldepryl, enalapril, Equanil, Plavix
Elavil may be confused with Elavil OTC (an over-the-counter sleep aid containing melatonin, valerian root, and vitamins).
Beers Criteria: Amitriptyline (alone or in combination) is identified in the Beers Criteria as a potentially inappropriate medication to be avoided in patients 65 years and older (independent of diagnosis or condition) due to its strong anticholinergic properties and potential for sedation and orthostatic hypotension. In addition, use TCAs with caution due to their potential to cause or exacerbate syndrome of inappropriate antidiuretic hormone secretion (SIADH) or hyponatremia; monitor sodium closely with initiation or dosage adjustments in older adults (Beers Criteria [AGS 2023]).
Amitriptyline is identified in the Screening Tool of Older Person's Prescriptions (STOPP) criteria as a potentially inappropriate medication in older adults (≥65 years of age) due to an increased risk of falls. Initiation is not recommended as first-line treatment for unipolar major depression. Additionally, disease states of concern include delirium, dementia, narrow angle glaucoma, cardiac conduction abnormalities, prostatism, chronic constipation, urinary retention, and orthostatic hypotension (O'Mahony 2023).
Substrate of CYP1A2 (Minor), CYP2B6 (Minor), CYP2C19 (Minor), CYP2C9 (Minor), CYP2D6 (Major), CYP3A4 (Minor); Note: Assignment of Major/Minor substrate status based on clinically relevant drug interaction potential;
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program
Acetylcholinesterase Inhibitors: May decrease therapeutic effects of Agents with Clinically Relevant Anticholinergic Effects. Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Acetylcholinesterase Inhibitors. Risk C: Monitor
Aclidinium: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid
Acrivastine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Acrivastine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Agents with Clinically Relevant Anticholinergic Effects: May increase anticholinergic effects of Tricyclic Antidepressants. Risk C: Monitor
Ajmaline: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Alcohol (Ethyl): CNS Depressants may increase CNS depressant effects of Alcohol (Ethyl). Risk C: Monitor
Alizapride: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Almotriptan: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Alosetron: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Alpha-/Beta-Agonists: Tricyclic Antidepressants may increase vasopressor effects of Alpha-/Beta-Agonists. Management: Avoid, if possible, the use of alpha-/beta-agonists in patients receiving tricyclic antidepressants. If combined, monitor for evidence of increased pressor effects and consider reductions in initial dosages of the alpha-/beta-agonist. Risk D: Consider Therapy Modification
Alpha1-Agonists: Tricyclic Antidepressants may increase therapeutic effects of Alpha1-Agonists. Tricyclic Antidepressants may decrease therapeutic effects of Alpha1-Agonists. Risk C: Monitor
Alpha2-Agonists (Ophthalmic): Tricyclic Antidepressants may decrease therapeutic effects of Alpha2-Agonists (Ophthalmic). Risk C: Monitor
Alpha2-Agonists: Tricyclic Antidepressants may decrease antihypertensive effects of Alpha2-Agonists. Management: Consider avoiding this combination. If used, monitor for decreased effects of the alpha2-agonist. Exercise great caution if discontinuing an alpha2-agonist in a patient receiving a TCA. Risk D: Consider Therapy Modification
Amantadine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Amifampridine: Agents With Seizure Threshold Lowering Potential may increase neuroexcitatory and/or seizure-potentiating effects of Amifampridine. Risk C: Monitor
Amisulpride (Oral): Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Amisulpride (Oral). Specifically, the risk of seizures may be increased. Risk C: Monitor
Amisulpride (Oral): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Amphetamines: Tricyclic Antidepressants may increase adverse/toxic effects of Amphetamines. Tricyclic Antidepressants may potentiate the cardiovascular effects of Amphetamines. Amphetamines may increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and increased cardiovascular effects when these agents are combined. Risk C: Monitor
Antiemetics (5HT3 Antagonists): May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
ARIPiprazole Lauroxil: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of ARIPiprazole Lauroxil. Specifically, the risk of seizures may be increased. Risk C: Monitor
ARIPiprazole: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of ARIPiprazole. Specifically, the risk of seizures may be increased. Risk C: Monitor
Artemether and Lumefantrine: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Articaine: May increase CNS depressant effects of CNS Depressants. Management: Consider reducing the dose of articaine if possible when used in patients who are also receiving CNS depressants. Monitor for excessive CNS depressant effects with any combined use. Risk D: Consider Therapy Modification
Asenapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Asenapine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Azelastine (Nasal): May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Baclofen: Tricyclic Antidepressants may increase adverse neuromuscular effects of Baclofen. Baclofen may increase CNS depressant effects of Tricyclic Antidepressants. Risk C: Monitor
Barbiturates: May increase metabolism of Tricyclic Antidepressants. Management: Monitor for decreased efficacy of tricyclic antidepressants if a barbiturate is initiated/dose increased, or increased effects if a barbiturate is discontinued/dose decreased. Tricyclic antidepressant dose adjustments are likely required. Risk D: Consider Therapy Modification
Benperidol: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Benperidol. Risk C: Monitor
Benperidol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Benperidol. Specifically, the risk of seizures may be increased. Risk C: Monitor
Benperidol: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Benztropine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Benztropine. Risk C: Monitor
Beta-Acetyldigoxin: Tricyclic Antidepressants may increase arrhythmogenic effects of Beta-Acetyldigoxin. Risk C: Monitor
Beta2-Agonists: Tricyclic Antidepressants may increase adverse/toxic effects of Beta2-Agonists. Risk C: Monitor
Biperiden: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Biperiden. Risk C: Monitor
Blonanserin: CNS Depressants may increase CNS depressant effects of Blonanserin. Management: Use caution if coadministering blonanserin and CNS depressants; dose reduction of the other CNS depressant may be required. Strong CNS depressants should not be coadministered with blonanserin. Risk D: Consider Therapy Modification
Bornaprine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Bornaprine. Risk C: Monitor
Botulinum Toxin-Containing Products: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Brexanolone: CNS Depressants may increase CNS depressant effects of Brexanolone. Risk C: Monitor
Brexpiprazole: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Brexpiprazole. Specifically, the risk of seizures may be increased. Risk C: Monitor
Brimonidine (Topical): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Bromopride: May increase adverse/toxic effects of Tricyclic Antidepressants. Risk X: Avoid
Bromperidol: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Buclizine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Buclizine. Risk C: Monitor
Buclizine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Buprenorphine: CNS Depressants may increase CNS depressant effects of Buprenorphine. Management: Consider reduced doses of other CNS depressants, and avoiding such drugs in patients at high risk of buprenorphine overuse/self-injection. Initiate buprenorphine at lower doses in patients already receiving CNS depressants. Risk D: Consider Therapy Modification
BuPROPion: Tricyclic Antidepressants may increase neuroexcitatory and/or seizure-potentiating effects of BuPROPion. BuPROPion may increase serum concentration of Tricyclic Antidepressants. Risk C: Monitor
BusPIRone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
BusPIRone: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Cannabinoid-Containing Products: Agents with Clinically Relevant Anticholinergic Effects may increase tachycardic effects of Cannabinoid-Containing Products. Risk C: Monitor
Cannabinoid-Containing Products: CNS Depressants may increase CNS depressant effects of Cannabinoid-Containing Products. Risk C: Monitor
CarBAMazepine: May decrease serum concentration of Tricyclic Antidepressants. Risk C: Monitor
Cariprazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Cariprazine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Cetirizine (Systemic): May increase CNS depressant effects of CNS Depressants. Management: Consider avoiding this combination if possible. If required, monitor for excessive sedation or CNS depression, limit the dose and duration of combination therapy, and consider CNS depressant dose reductions. Risk D: Consider Therapy Modification
Chloral Hydrate/Chloral Betaine: CNS Depressants may increase CNS depressant effects of Chloral Hydrate/Chloral Betaine. Management: Consider alternatives to the use of chloral hydrate or chloral betaine and additional CNS depressants. If combined, consider a dose reduction of either agent and monitor closely for enhanced CNS depressive effects. Risk D: Consider Therapy Modification
Chlormethiazole: May increase CNS depressant effects of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. Risk D: Consider Therapy Modification
Chlorphenesin Carbamate: May increase adverse/toxic effects of CNS Depressants. Risk C: Monitor
ChlorproMAZINE: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of ChlorproMAZINE. Specifically, the risk of seizures may be increased. Risk C: Monitor
Chlorprothixene: May increase QTc-prolonging effects of Tricyclic Antidepressants. Risk X: Avoid
Cimetidine: May increase serum concentration of Tricyclic Antidepressants. Risk C: Monitor
Cimetropium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Cimetropium. Risk X: Avoid
Cisapride: Amitriptyline may increase arrhythmogenic effects of Cisapride. Risk X: Avoid
Citalopram: Tricyclic Antidepressants may increase serotonergic effects of Citalopram. Tricyclic Antidepressants may increase serum concentration of Citalopram. Citalopram may increase serum concentration of Tricyclic Antidepressants. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and increased TCA and citalopram concentrations/effects. Risk C: Monitor
Clothiapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Clothiapine. Specifically, the risk of seizures may be increased. Risk C: Monitor
CloZAPine: Agents with Clinically Relevant Anticholinergic Effects may increase constipating effects of CloZAPine. Management: Consider alternatives to this combination whenever possible. If combined, monitor closely for signs and symptoms of gastrointestinal hypomotility and consider prophylactic laxative treatment. Risk D: Consider Therapy Modification
CNS Depressants: May increase adverse/toxic effects of CNS Depressants. Risk C: Monitor
Cocaine (Topical): May increase adverse/toxic effects of Tricyclic Antidepressants. Risk C: Monitor
Cyclizine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Cyclobenzaprine: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
CYP2D6 Inhibitors (Moderate): May increase serum concentration of Amitriptyline. CYP2D6 Inhibitors (Moderate) may increase active metabolite exposure of Amitriptyline. Risk C: Monitor
CYP2D6 Inhibitors (Strong): May increase serum concentration of Amitriptyline. CYP2D6 Inhibitors (Strong) may increase active metabolite exposure of Amitriptyline. Risk C: Monitor
Dantrolene: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Dapoxetine: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Do not use serotonergic agents (high risk) with dapoxetine or within 7 days of serotonergic agent discontinuation. Do not use dapoxetine within 14 days of monoamine oxidase inhibitor use. Dapoxetine labeling lists this combination as contraindicated. Risk X: Avoid
Daridorexant: May increase CNS depressant effects of CNS Depressants. Management: Dose reduction of daridorexant and/or any other CNS depressant may be necessary. Use of daridorexant with alcohol is not recommended, and the use of daridorexant with any other drug to treat insomnia is not recommended. Risk D: Consider Therapy Modification
Darifenacin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Darifenacin. Risk C: Monitor
Desmopressin: Tricyclic Antidepressants may increase hyponatremic effects of Desmopressin. Risk C: Monitor
DexmedeTOMIDine: CNS Depressants may increase CNS depressant effects of DexmedeTOMIDine. Management: Monitor for increased CNS depression during coadministration of dexmedetomidine and CNS depressants, and consider dose reductions of either agent to avoid excessive CNS depression. Risk D: Consider Therapy Modification
Dexmethylphenidate-Methylphenidate: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Dextromethorphan: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Dicyclomine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Dicyclomine. Risk C: Monitor
Difelikefalin: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Difenoxin: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Dihydralazine: CNS Depressants may increase hypotensive effects of Dihydralazine. Risk C: Monitor
Dimethindene (Systemic): Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Dimethindene (Systemic). Risk C: Monitor
Dimethindene (Topical): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Dothiepin: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Doxylamine: CNS Depressants may increase CNS depressant effects of Doxylamine. Risk C: Monitor
DroNABinol: Agents with Clinically Relevant Anticholinergic Effects may increase tachycardic effects of DroNABinol. Risk X: Avoid
Dronedarone: Tricyclic Antidepressants may increase arrhythmogenic effects of Dronedarone. Risk X: Avoid
DroPERidol: May increase CNS depressant effects of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (eg, opioids, barbiturates) with concomitant use. Risk D: Consider Therapy Modification
DULoxetine: May increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. DULoxetine may increase serum concentration of Tricyclic Antidepressants. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and increased TCA concentrations and effects if these agents are combined. Risk C: Monitor
Eletriptan: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Eluxadoline: Agents with Clinically Relevant Anticholinergic Effects may increase constipating effects of Eluxadoline. Risk X: Avoid
Emedastine (Systemic): May increase CNS depressant effects of CNS Depressants. Management: Consider avoiding this combination if possible. If required, monitor for excessive sedation or CNS depression, limit the dose and duration of combination therapy, and consider CNS depressant dose reductions. Risk C: Monitor
Entacapone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Epinephrine (Racemic): Tricyclic Antidepressants may increase adverse/toxic effects of Epinephrine (Racemic). Risk X: Avoid
Ergot Derivatives: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Escitalopram: Tricyclic Antidepressants may increase serotonergic effects of Escitalopram. Escitalopram may increase serum concentration of Tricyclic Antidepressants. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and increased TCA concentrations/effects if these agents are combined. Risk C: Monitor
Esketamine (Nasal): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Fenfluramine: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Risk C: Monitor
Fesoterodine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Fesoterodine. Risk C: Monitor
Fluconazole: Amitriptyline may increase QTc-prolonging effects of Fluconazole. Fluconazole may increase serum concentration of Amitriptyline. Risk C: Monitor
Flunarizine: CNS Depressants may increase CNS depressant effects of Flunarizine. Risk X: Avoid
Flunitrazepam: CNS Depressants may increase CNS depressant effects of Flunitrazepam. Management: Reduce the dose of CNS depressants when combined with flunitrazepam and monitor patients for evidence of CNS depression (eg, sedation, respiratory depression). Use non-CNS depressant alternatives when available. Risk D: Consider Therapy Modification
FLUoxetine: May increase serotonergic effects of Tricyclic Antidepressants. FLUoxetine may increase serum concentration of Tricyclic Antidepressants. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and increased TCA concentrations/effects if these agents are combined. Risk D: Consider Therapy Modification
Flupentixol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Flupentixol. Specifically, the risk of seizures may be increased. Risk C: Monitor
FluPHENAZine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of FluPHENAZine. Specifically, the risk of seizures may be increased. Risk C: Monitor
FluPHENAZine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
FluvoxaMINE: May increase serotonergic effects of Tricyclic Antidepressants. FluvoxaMINE may increase serum concentration of Tricyclic Antidepressants. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and increased TCA concentrations/effects if these agents are combined. Risk C: Monitor
Gastrointestinal Agents (Prokinetic): Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Gastrointestinal Agents (Prokinetic). Risk C: Monitor
Gepirone: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Risk C: Monitor
Gepotidacin: May decrease anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Glucagon: Agents with Clinically Relevant Anticholinergic Effects may increase adverse/toxic effects of Glucagon. Specifically, the risk of gastrointestinal adverse effects may be increased. Risk C: Monitor
Glycopyrrolate (Oral Inhalation): Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Glycopyrrolate (Oral Inhalation). Risk X: Avoid
Glycopyrrolate (Systemic): Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Glycopyrrolate (Systemic). Risk C: Monitor
Glycopyrronium (Topical): May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid
Guanethidine: Tricyclic Antidepressants may decrease therapeutic effects of Guanethidine. Risk C: Monitor
Haloperidol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Haloperidol. Specifically, the risk of seizures may be increased. Risk C: Monitor
Haloperidol: QT-prolonging Agents (Indeterminate Risk - Caution) may increase QTc-prolonging effects of Haloperidol. Risk C: Monitor
HydrOXYzine: May increase CNS depressant effects of CNS Depressants. Management: Consider a decrease in the CNS depressant dose, as appropriate, when used together with hydroxyzine. Increase monitoring of signs/symptoms of CNS depression in any patient receiving hydroxyzine together with another CNS depressant. Risk D: Consider Therapy Modification
Iloperidone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Iloperidone. Specifically, the risk of seizures may be increased. Risk C: Monitor
Iobenguane Radiopharmaceutical Products: Tricyclic Antidepressants may decrease therapeutic effects of Iobenguane Radiopharmaceutical Products. Management: Discontinue all drugs that may inhibit or interfere with catecholamine transport or uptake for at least 5 biological half-lives before iobenguane administration. Do not administer these drugs until at least 7 days after each iobenguane dose. Risk X: Avoid
Iohexol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Iohexol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iohexol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic antiseizure drugs. Risk D: Consider Therapy Modification
Iomeprol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Iomeprol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iomeprol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic antiseizure drugs. Risk D: Consider Therapy Modification
Iopamidol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Iopamidol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iopamidol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic antiseizure drugs. Risk D: Consider Therapy Modification
Ipratropium (Nasal): May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Ipratropium (Oral Inhalation): May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid
Itopride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Itopride. Risk C: Monitor
Ixabepilone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Kava Kava: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Ketotifen (Systemic): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Kratom: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Lasmiditan: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Lemborexant: May increase CNS depressant effects of CNS Depressants. Management: Dosage adjustments of lemborexant and of concomitant CNS depressants may be necessary when administered together because of potentially additive CNS depressant effects. Close monitoring for CNS depressant effects is necessary. Risk D: Consider Therapy Modification
Levocetirizine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Levosulpiride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Levosulpiride. Risk X: Avoid
Linezolid: May increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Risk X: Avoid
Lisuride: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Lofepramine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Lofexidine: Tricyclic Antidepressants may decrease therapeutic effects of Lofexidine. Management: Consider avoiding this drug combination when possible. If concurrent administration is required, monitor blood pressure carefully at the beginning of the combined therapy and when either drug is stopped. Adjust the dosage accordingly. Risk D: Consider Therapy Modification
Loxapine: CNS Depressants may increase CNS depressant effects of Loxapine. Management: Consider reducing the dose of CNS depressants administered concomitantly with loxapine due to an increased risk of respiratory depression, sedation, hypotension, and syncope. Risk D: Consider Therapy Modification
Lumateperone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Lumateperone. Specifically, the risk of seizures may be increased. Risk C: Monitor
Lurasidone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Lurasidone. Specifically, the risk of seizures may be increased. Risk C: Monitor
Magnesium Sulfate: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Maprotiline: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Maprotiline. Risk C: Monitor
Mavorixafor: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk X: Avoid
Melitracen [INT]: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Melperone: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Melperone: Tricyclic Antidepressants may increase adverse/toxic effects of Melperone. Melperone may increase adverse/toxic effects of Tricyclic Antidepressants. Melperone may increase serum concentration of Tricyclic Antidepressants. Risk C: Monitor
Mequitazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Metaxalone: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Metergoline: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Methotrimeprazine: CNS Depressants may increase CNS depressant effects of Methotrimeprazine. Methotrimeprazine may increase CNS depressant effects of CNS Depressants. Management: Reduce the usual dose of CNS depressants by 50% if starting methotrimeprazine until the dose of methotrimeprazine is stable. Monitor patient closely for evidence of CNS depression. Risk D: Consider Therapy Modification
Methoxyflurane: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Methscopolamine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Methscopolamine. Risk C: Monitor
Methylene Blue: Tricyclic Antidepressants may increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid
Metoclopramide: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Metoclopramide: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Consider monitoring for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
MetyroSINE: CNS Depressants may increase sedative effects of MetyroSINE. Risk C: Monitor
Minocycline (Systemic): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Mirabegron: Agents with Clinically Relevant Anticholinergic Effects may increase adverse/toxic effects of Mirabegron. Risk C: Monitor
Molindone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Molindone. Specifically, the risk of seizures may be increased. Risk C: Monitor
Monoamine Oxidase Inhibitors (Antidepressant): May increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Risk X: Avoid
Nabilone: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Nalfurafine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Nefazodone: Tricyclic Antidepressants may increase serotonergic effects of Nefazodone. This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Nicorandil: Tricyclic Antidepressants may increase hypotensive effects of Nicorandil. Risk C: Monitor
Nitroglycerin: Agents with Clinically Relevant Anticholinergic Effects may decrease absorption of Nitroglycerin. Specifically, anticholinergic agents may decrease the dissolution of sublingual nitroglycerin tablets, possibly impairing or slowing nitroglycerin absorption. Risk C: Monitor
Nonsteroidal Anti-Inflammatory Agents: Tricyclic Antidepressants may increase antiplatelet effects of Nonsteroidal Anti-Inflammatory Agents. Tricyclic Antidepressants may increase adverse/toxic effects of Nonsteroidal Anti-Inflammatory Agents. Specifically, the risk of major adverse cardiac events (MACE), hemorrhagic stroke, ischemic stroke, and heart failure may be increased. Risk C: Monitor
Noscapine: CNS Depressants may increase adverse/toxic effects of Noscapine. Risk X: Avoid
OLANZapine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of OLANZapine. Risk C: Monitor
OLANZapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of OLANZapine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Olopatadine (Nasal): May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Ondansetron: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Opicapone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Opioid Agonists: CNS Depressants may increase CNS depressant effects of Opioid Agonists. Management: Avoid concomitant use of opioid agonists and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Risk D: Consider Therapy Modification
Opipramol: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Opipramol: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Opipramol: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Orphenadrine: CNS Depressants may increase CNS depressant effects of Orphenadrine. Risk X: Avoid
Oxatomide: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid
Oxitriptan: Serotonergic Agents (High Risk) may increase serotonergic effects of Oxitriptan. This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Oxomemazine: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Oxybate Salt Products: CNS Depressants may increase CNS depressant effects of Oxybate Salt Products. Management: Consider alternatives to this combination when possible. If combined, dose reduction or discontinuation of one or more CNS depressants (including the oxybate salt product) should be considered. Interrupt oxybate salt treatment during short-term opioid use Risk D: Consider Therapy Modification
OxyBUTYnin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of OxyBUTYnin. Risk C: Monitor
OxyCODONE: CNS Depressants may increase CNS depressant effects of OxyCODONE. Management: Avoid concomitant use of oxycodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Risk D: Consider Therapy Modification
Paliperidone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Paliperidone. Specifically, the risk of seizures may be increased. Risk C: Monitor
Paliperidone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Paraldehyde: CNS Depressants may increase CNS depressant effects of Paraldehyde. Risk X: Avoid
PARoxetine: May increase serotonergic effects of Tricyclic Antidepressants. PARoxetine may increase serum concentration of Tricyclic Antidepressants. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and increased TCA concentrations/effects if these agents are combined. Risk D: Consider Therapy Modification
Peginterferon Alfa-2b: May decrease serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Peginterferon Alfa-2b may increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Perampanel: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Perazine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Periciazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Periciazine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Periciazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Perphenazine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Perphenazine. Risk C: Monitor
Perphenazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Perphenazine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Pimozide: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Pimozide. Specifically, the risk of seizures may be increased. Risk C: Monitor
Pipamperone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Pipamperone. Specifically, the risk of seizures may be increased. Risk X: Avoid
Piribedil: CNS Depressants may increase CNS depressant effects of Piribedil. Risk C: Monitor
Pitolisant: Tricyclic Antidepressants may decrease therapeutic effects of Pitolisant. Risk X: Avoid
Pizotifen: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Polyethylene Glycol-Electrolyte Solution: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Polyethylene Glycol-Electrolyte Solution. Specifically, the risk of seizure may be increased. Risk C: Monitor
Potassium Chloride: Agents with Clinically Relevant Anticholinergic Effects may increase ulcerogenic effects of Potassium Chloride. Management: Patients on drugs with substantial anticholinergic effects should avoid using any solid oral dosage form of potassium chloride. Risk X: Avoid
Potassium Citrate: Agents with Clinically Relevant Anticholinergic Effects may increase ulcerogenic effects of Potassium Citrate. Management: Patients on drugs with substantial anticholinergic effects should avoid using any solid oral dosage form of potassium citrate. Risk X: Avoid
Pramipexole: CNS Depressants may increase sedative effects of Pramipexole. Risk C: Monitor
Pramlintide: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. These effects are specific to the GI tract. Risk X: Avoid
Procarbazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Prochlorperazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Prochlorperazine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Promazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Promazine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Promethazine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Promethazine. Risk C: Monitor
Propantheline: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Propantheline. Risk C: Monitor
Propiverine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Psilocybin: Antidepressants may decrease therapeutic effects of Psilocybin. Risk C: Monitor
QT-prolonging Agents (Highest Risk): QT-prolonging Agents (Indeterminate Risk - Caution) may increase QTc-prolonging effects of QT-prolonging Agents (Highest Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Risk C: Monitor
QUEtiapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of QUEtiapine. Specifically, the risk of seizures may be increased. Risk C: Monitor
QuiNIDine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Ramosetron: Agents with Clinically Relevant Anticholinergic Effects may increase constipating effects of Ramosetron. Risk C: Monitor
Ramosetron: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Rasagiline: May increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Risk X: Avoid
Revefenacin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Revefenacin. Risk X: Avoid
RifAMPin: May decrease serum concentration of Amitriptyline. RifAMPin may decrease active metabolite exposure of Amitriptyline. Specifically, concentrations of nortriptyline may be reduced. Risk C: Monitor
Rifapentine: May decrease active metabolite exposure of Amitriptyline. Specifically, concentrations of nortriptyline may be reduced. Rifapentine may decrease serum concentration of Amitriptyline. Risk C: Monitor
RisperiDONE: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of RisperiDONE. Specifically, the risk of seizures may be increased. Risk C: Monitor
Rivastigmine: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Rivastigmine. Rivastigmine may decrease therapeutic effects of Agents with Clinically Relevant Anticholinergic Effects. Management: Use of rivastigmine with an anticholinergic agent is not recommended unless clinically necessary. If the combination is necessary, monitor for reduced anticholinergic effects. Risk D: Consider Therapy Modification
Ropeginterferon Alfa-2b: CNS Depressants may increase adverse/toxic effects of Ropeginterferon Alfa-2b. Specifically, the risk of neuropsychiatric adverse effects may be increased. Management: Avoid coadministration of ropeginterferon alfa-2b and other CNS depressants. If this combination cannot be avoided, monitor patients for neuropsychiatric adverse effects (eg, depression, suicidal ideation, aggression, mania). Risk D: Consider Therapy Modification
ROPINIRole: CNS Depressants may increase sedative effects of ROPINIRole. Risk C: Monitor
Rotigotine: CNS Depressants may increase sedative effects of Rotigotine. Risk C: Monitor
Safinamide: May increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Risk X: Avoid
Scopolamine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Scopolamine. Risk C: Monitor
Secretin: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Secretin. Management: Avoid concomitant use of anticholinergic agents and secretin. Discontinue anticholinergic agents at least 5 half-lives prior to administration of secretin. Risk D: Consider Therapy Modification
Selegiline: May increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Risk X: Avoid
Serotonergic Agents (High Risk, Miscellaneous): Tricyclic Antidepressants may increase serotonergic effects of Serotonergic Agents (High Risk, Miscellaneous). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Serotonergic Non-Opioid CNS Depressants: Tricyclic Antidepressants may increase serotonergic effects of Serotonergic Non-Opioid CNS Depressants. This could result in serotonin syndrome. Tricyclic Antidepressants may increase CNS depressant effects of Serotonergic Non-Opioid CNS Depressants. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and CNS depression when these agents are combined. Risk C: Monitor
Serotonergic Opioids (High Risk): May increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Tricyclic Antidepressants may increase CNS depressant effects of Serotonergic Opioids (High Risk). Management: Consider alternatives to this drug combination. If combined, monitor for signs and symptoms of serotonin syndrome/serotonin toxicity and CNS depression. Risk D: Consider Therapy Modification
Serotonin 5-HT1D Receptor Agonists (Triptans): May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Serotonin/Norepinephrine Reuptake Inhibitor: May increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes when these agents are combined. Risk C: Monitor
Sertindole: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Sertindole. Specifically, the risk of seizures may be increased. Risk C: Monitor
Sertraline: May increase serotonergic effects of Tricyclic Antidepressants. Sertraline may increase serum concentration of Tricyclic Antidepressants. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and increased TCA concentrations/effects if these agents are combined. Risk C: Monitor
Sodium Phosphates: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Sodium Phosphates. Specifically, the risk of seizure or loss of consciousness may be increased in patients with significant sodium phosphate-induced fluid or electrolyte abnormalities. Risk C: Monitor
Sofpironium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Sofpironium. Risk X: Avoid
St John's Wort: May increase serotonergic effects of Amitriptyline. This could result in serotonin syndrome. St John's Wort may decrease serum concentration of Amitriptyline. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) and reduced amitriptyline concentrations when these agents are combined. Risk C: Monitor
Sulpiride: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Sulpiride. Specifically, the risk of seizures may be increased. Risk C: Monitor
Suvorexant: CNS Depressants may increase CNS depressant effects of Suvorexant. Management: Dose reduction of suvorexant and/or any other CNS depressant may be necessary. Use of suvorexant with alcohol is not recommended, and the use of suvorexant with any other drug to treat insomnia is not recommended. Risk D: Consider Therapy Modification
Syrian Rue: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor
Thalidomide: CNS Depressants may increase CNS depressant effects of Thalidomide. Risk X: Avoid
Thiazide and Thiazide-Like Diuretics: Agents with Clinically Relevant Anticholinergic Effects may increase serum concentration of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Thioridazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Thioridazine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Thiothixene: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Thiothixene. Risk C: Monitor
Thiothixene: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Thiothixene. Specifically, the risk of seizures may be increased. Risk C: Monitor
Thyroid Products: May increase arrhythmogenic effects of Tricyclic Antidepressants. Thyroid Products may increase stimulatory effects of Tricyclic Antidepressants. Risk C: Monitor
Tiapride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Tiapride. Risk C: Monitor
Tiotropium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Tiotropium. Risk X: Avoid
Tolterodine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Tolterodine. Risk C: Monitor
Topiramate: May increase CNS depressant effects of Amitriptyline. Topiramate may increase serum concentration of Amitriptyline. Topiramate may increase active metabolite exposure of Amitriptyline. Risk C: Monitor
Tricyclic Antidepressants: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Tricyclic Antidepressants. Risk C: Monitor
Tricyclic Antidepressants: May increase anticholinergic effects of Tricyclic Antidepressants. Tricyclic Antidepressants may increase CNS depressant effects of Tricyclic Antidepressants. Tricyclic Antidepressants may increase serotonergic effects of Tricyclic Antidepressants. This could result in serotonin syndrome. Management: Monitor closely for increased TCA adverse effects, including serotonin syndrome/serotonin toxicity, CNS depression, and anticholinergic effects. Risk C: Monitor
Trifluoperazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Trifluoperazine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Trimeprazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Trimethobenzamide: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Trimethobenzamide. Risk C: Monitor
Trospium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Trospium. Risk C: Monitor
Umeclidinium: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid
Valerian: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Valproic Acid and Derivatives: May increase serum concentration of Tricyclic Antidepressants. Risk C: Monitor
Vasopressin: Drugs Suspected of Causing SIADH may increase therapeutic effects of Vasopressin. Specifically, the pressor and antidiuretic effects of vasopressin may be increased. Risk C: Monitor
Vilazodone: Tricyclic Antidepressants may increase serotonergic effects of Vilazodone. This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) if these agents are combined. Risk C: Monitor
Vitamin K Antagonists: Amitriptyline may increase anticoagulant effects of Vitamin K Antagonists. Risk C: Monitor
Vortioxetine: Tricyclic Antidepressants may increase serotonergic effects of Vortioxetine. This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) if these agents are combined. Risk C: Monitor
Ziprasidone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Ziprasidone. Specifically, the risk of seizures may be increased. Risk C: Monitor
Ziprasidone: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Risk C: Monitor
Zolpidem: CNS Depressants may increase CNS depressant effects of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. Risk D: Consider Therapy Modification
Zuclopenthixol: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Zuclopenthixol. Risk C: Monitor
Zuclopenthixol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Zuclopenthixol. Specifically, the risk of seizures may be increased. Risk C: Monitor
Zuranolone: May increase CNS depressant effects of CNS Depressants. Management: Consider alternatives to the use of zuranolone with other CNS depressants or alcohol. If combined, consider a zuranolone dose reduction and monitor patients closely for increased CNS depressant effects. Risk D: Consider Therapy Modification
Evaluate pregnancy status prior to initiating treatment in patients who could become pregnant. Treatment should not be withheld, but pharmacologic management may vary based on reproductive status, severity of illness, and history of antidepressant response (ACOG 2023; WFSBP [Dodd 2018]). When treating depression, tricyclic antidepressants are not first-line medications for use prior to conception in patients who are treatment naive or who do not have a history of effective treatment. Patients effectively treated may continue their current medication when planning a pregnancy unless contraindications exist (BAP [McAllister-Williams 2017]). Management of mental health conditions in patients who could become pregnant should be based on a shared decision-making process that considers the possibility of pregnancy during treatment (ACOG 2023; BAP [McAllister-Williams 2017]; CANMAT [MacQueen 2016]).
Amitriptyline may be effective for prevention of migraines. In general, preventive treatment for migraine in patients trying to become pregnant should be avoided. Options for patients planning a pregnancy should be considered as part of a shared decision-making process. Nonpharmacologic interventions should be considered initially. When needed, preventive treatment should be individualized considering the available safety data and needs of the patient should pregnancy occur. A gradual discontinuation of preventive medications is generally preferred when the decision is made to stop treatment prior to conception (ACOG 2022; AHS [Ailani 2021]).
Amitriptyline crosses the human placenta.
Outcome data following maternal use of tricyclic antidepressants (TCAs), including amitriptyline during pregnancy are available (Altshuler 1996; Bérard 2017; Cantarutti 2017; De Vries 2021; Ericson 1999; Huybrechts 2015; McDonagh 2014; McElhatton 1996). Study outcomes vary due to limited data, differences in study design, and confounders (Gentile 2014; Yonkers 2014). According to the manufacturer, CNS effects, limb deformities, and developmental delay have been noted in case reports (causal relationship not established).
Preliminary data suggest amitriptyline may be associated with an increased risk of developing gestational diabetes mellitus (GDM). Additional studies are needed (Dandjinou 2019; Wang 2023). Screening for GDM should continue as part of standard prenatal care; early screening is not needed due to psychiatric medication exposure (ACOG 2023).
Due to pregnancy-induced physiologic changes some pharmacokinetic parameters of amitriptyline may be altered; maternal serum concentrations may decrease as pregnancy progresses (Leutritz 2023). Data are insufficient to make recommendation; however, therapeutic drug monitoring of TCAs can be considered during pregnancy and postpartum to avoid toxicity and monitor efficacy (Deligiannidis 2014).
Untreated and undertreated mental health conditions are associated with adverse pregnancy outcomes. Untreated or undertreated depression is associated with preterm birth, low-birth-weight, preeclampsia, postpartum depression, and impaired infant attachment (associated with long-term developmental effects). Discontinuing effective medications during pregnancy increases the risk of relapse. Management of mental health conditions should be made as part of a shared decision-making process (ACOG 2023). Patients effectively treated for depression pre-pregnancy may use the same medication during pregnancy unless contraindications exist (ACOG 2023; BAP [McAllister-Williams 2017]; CANMAT [MacQueen 2016]). Treatment should not be withheld or discontinued based only on pregnancy status (ACOG 2023). TCAs are not considered first-line medications for pregnant patients who are treatment naive or who do not have a history of effective treatment with another medication (ACOG 2023; BAP [McAllister-Williams 2017]; CANMAT [MacQueen 2016]) but may be considered as an alternative (CANMAT [MacQueen 2016]). When medications are used, the lowest effective dose of a single agent is recommended. Optimize dosing prior to changing a medication or adding additional agents whenever possible. Close monitoring for symptom improvement with a validated screening tool during pregnancy is recommended. Manage side effects as needed (ACOG 2023).
In general, preventive treatment for migraine should be avoided during pregnancy. Options for pregnant patients should be considered as part of a shared decision-making process. Nonpharmacologic interventions should be considered initially. When needed, preventive treatment should be individualized considering the available safety data, the potential for adverse maternal and fetal events, and needs of the patient (ACOG 2022; AHS [Ailani 2021]). Efficacy data of amitriptyline for migraine prevention in pregnancy are limited and use is not recommended (ACOG 2022). Amitriptyline may be used if other agents are ineffective or contraindicated, considering the risks and benefits of use (ACOG 2022; CHS [Pringsheim 2012]).
The use of amitriptyline to treat cyclic vomiting syndrome in a pregnant patient has been described in a case report (Tamai 2015).
Data collection to monitor pregnancy and infant outcomes following exposure to antidepressant medications is ongoing. Encourage pregnant patients 45 years of age and younger with a history of psychiatric illness to enroll in the National Pregnancy Registry for Antidepressants (1-866-961-2388 or https://womensmentalhealth.org/research/pregnancyregistry/antidepressants).
Heart rate, blood pressure, mental status, weight. Monitor patient periodically for symptom resolution; monitor for worsening depression, suicidality, and associated behaviors (especially at the beginning of therapy or when doses are increased or decreased).
Note: Plasma levels do not always correlate with clinical effectiveness.
Timing of serum samples: Draw trough just before next dose (Hiemke 2018), with once-daily bedtime dosing draw level 12 to 16 hours after dose (Ziegler 1977).
Therapeutic reference range: Amitriptyline plus nortriptyline 80 to 200 ng/mL (SI: 288 to 720 nmol/L).
Increases the synaptic concentration of serotonin and/or norepinephrine in the central nervous system by inhibition of their reuptake by the presynaptic neuronal membrane pump.
Onset of action: Depression: Initial effects may be observed within 1 to 2 weeks of treatment with continued improvements through 4 to 6 weeks (Papakostas 2006; Posternak 2005; Szegedi 2009).
Absorption: Rapid, well absorbed.
Distribution: Vd: ~18 to 22 L/kg (Schulz 1985).
Protein binding: >90%.
Metabolism: Rapid; hepatic N to demethylation to nortriptyline (active), hydroxy derivatives and conjugated derivatives.
Bioavailability: ~43% to 46% (Schulz 1985).
Half-life elimination: ~13 to 36 hours (Schulz 1985).
Time to peak, serum: ~2 to 5 hours (Schulz 1985).
Excretion: Urine (glucuronide or sulfate conjugate metabolites; little as unchanged drug); Feces (small amounts).
Special Populations: Older adults: May have increased plasma levels (Schulz 1985).
Older adult: May have increased plasma levels and prolonged half-life (Schulz 1985).
Sex: In women over 50 years of age, plasma amitriptyline concentrations were higher than males in the same age group (Preskorn 1985).
Hepatic function impairment: Plasma levels and AUC approximately tripled in a patient with portocaval anastomosis and liver cirrhosis (Hrdina 1985).
