Version July 2025
Loxapine inhalation can cause bronchospasm that has the potential to lead to respiratory distress and respiratory arrest, particularly in patients with lung diseases. Administer loxapine inhalation only in a certified health care setting that has immediate access on site to supplies and health care professionals competent in the management of acute bronchospasm and access to emergency assistance for symptoms that require immediate medical attention. Certified health care settings must have a short-acting bronchodilator (eg, albuterol) available for the immediate treatment of bronchospasm; this short-acting bronchodilator can be delivered by inhaler (with spacer) or nebulizer. Prior to administering loxapine inhalation, screen patients regarding a current diagnosis, history, or symptoms of asthma, chronic obstructive pulmonary disease (COPD), and other lung diseases, and assess (including chest auscultation) patients for respiratory signs. Monitor for signs and symptoms of bronchospasm following treatment with loxapine inhalation.
Because of the risk of bronchospasm, loxapine inhalation is available only through a restricted program under a risk evaluation and mitigation strategy (REMS) called the Adasuve REMS.
Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Loxapine is not approved for the treatment of patients with dementia-related psychosis.
Dosage guidance:
Safety: Antipsychotics are not indicated for use in catatonia and may worsen psychosis and increase the risk for neuroleptic malignant syndrome in patients with catatonia (Ref).
Clinical considerations: Consult a psychiatry specialist for all management decisions; select antipsychotic carefully based on patient preference, clinical characteristics, history, comorbidities, and adverse effect profile (Ref).
Agitation, acute, associated with schizophrenia or bipolar I disorder:
Inhalation: 10 mg once daily; maximum dose: 10 mg per 24-hour period.
IM [Canadian product]: 12.5 to 50 mg every 4 to 12 hours, as needed, based on response and tolerability (Ref).
Schizophrenia:
Note: Some experts prefer second generation antipsychotics for initial treatment due to the potential for fewer extrapyramidal symptoms (Ref); data suggesting differences in efficacy are lacking (Ref).
Oral: Initial: 10 mg twice daily, or if this is a first episode of psychosis, consider initiating at a reduced dose (eg, 5 mg twice daily) because these patients will be more sensitive to adverse effects. May increase daily dose in increments of 10 mg every 3 to 5 days based on response and tolerability to the usual range of 20 to 100 mg/day in 1 or 2 divided doses. Monitor for akathisia, anticholinergic effects, orthostatic hypotension, parkinsonism and sedation during titration. Maximum: 250 mg/day (Ref).
Discontinuation of therapy: In the treatment of chronic psychiatric disease, switching therapy rather than discontinuation is generally advised if side effects are intolerable or treatment is not effective. If patient insists on stopping treatment, gradual dose reduction of oral dose (ie, over several weeks to months) is advised to detect a re-emergence of symptoms and to avoid withdrawal reactions (eg, agitation, alternating feelings of warmth and chill, anxiety, diaphoresis, dyskinesias, GI symptoms, insomnia, irritability, myalgia, paresthesia, psychosis, restlessness, rhinorrhea, tremor, vertigo) unless discontinuation is due to significant adverse effects. Monitor closely to allow for detection of prodromal symptoms of disease recurrence (Ref).
Switching antipsychotics: An optimal universal strategy for switching antipsychotic drugs has not been established. Strategies include cross-titration (gradually discontinuing the first antipsychotic while gradually increasing the new antipsychotic) and abrupt change (abruptly discontinuing the first antipsychotic and either increasing the new antipsychotic gradually or starting it at a treatment dose). In patients with schizophrenia at high risk of relapse, the current medication may be maintained at full dose as the new medication is increased (ie, overlap); once the new medication is at therapeutic dose, the first medication is gradually decreased and discontinued over 1 to 2 weeks (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Inhalation: No dosage adjustment necessary.
Oral: There are no dosage adjustments provided in the manufacturer’s labeling.
Inhalation: No dosage adjustment necessary.
Oral: There are no dosage adjustments provided in the manufacturer’s labeling.
Note: Avoid for behavioral problems associated with dementia or delirium unless alternative nonpharmacologic therapies have failed and patient may harm self or others. If used, consider deprescribing attempts to assess continued need and/or lowest effective dose. Of note: use in certain indications may be appropriate (eg, schizophrenia, bipolar disorder) (Ref). Consult a psychiatry specialist for all management decisions (Ref).
All indications: Refer to adult dosing. Dosages in the lower range of recommended adult dosing are generally sufficient with late-onset schizophrenia or psychosis. Titrate dosage slowly and monitor carefully (Ref).
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
Inhalation:
>10%:
Gastrointestinal: Dysgeusia (14%)
Nervous system: Sedated state (12%)
Respiratory: Respiratory distress (asthma patients: 54%; COPD patients: 19%; includes bronchospasm, chest pain, cough, dyspnea, pharyngeal edema, wheezing)
1% to 10%:
Cardiovascular: Hypotension (3%), syncope (2%)
Respiratory: Throat irritation (3%)
<1%: Nervous system: Extrapyramidal reaction
Frequency not defined: Hypersensitivity: Hypersensitivity reaction
Oral:
Frequency not defined:
Cardiovascular: ECG changes, edema, flushing (facial), hypertension, hypotension, orthostatic hypotension, syncope, tachycardia
Dermatologic: Alopecia, dermatitis, pruritus, seborrhea, skin photosensitivity, skin rash
Endocrine & metabolic: Amenorrhea, galactorrhea not associated with childbirth, gynecomastia, hyperprolactinemia, menstrual disease, polydipsia, weight gain, weight loss
Gastrointestinal: Constipation, nausea, paralytic ileus, vomiting, xerostomia
Genitourinary: Impotence, priapism (rare), urinary retention
Hematologic & oncologic: Agranulocytosis, leukopenia, thrombocytopenia
Hepatic: Hepatitis, increased serum alanine aminotransferase, increased serum aspartate aminotransferase, jaundice
Nervous system: Agitation, confusion, disruption of body temperature regulation, dizziness, drowsiness, extrapyramidal reaction (akathisia, akinesia, dystonia, drug-induced Parkinson's disease, tardive dyskinesia), headache, hyperpyrexia, insomnia, neuroleptic malignant syndrome, numbness, paresthesia, sedated state, seizure, slurred speech, tension, unsteady gait
Neuromuscular & skeletal: Asthenia, muscle twitching
Ophthalmic: Blepharoptosis, blurred vision
Respiratory: Dyspnea, nasal congestion
Postmarketing (any route): Cardiovascular: Atrial fibrillation (Chou 2017), atrial flutter (Chou 2017)
Oral: Hypersensitivity to loxapine or any component of the formulation; severe drug-induced CNS depression; coma.
Inhalation: Known hypersensitivity to loxapine, amoxapine, or any component of the formulation; current diagnosis or history of asthma, COPD, or other lung disease associated with bronchospasm; acute respiratory symptoms or signs (eg, wheezing); current use of medications to treat airways disease, such as asthma or COPD; history of bronchospasm following loxapine treatment.
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Canadian labeling: Additional contraindication (not in US labeling): Oral, IM: Circulatory collapse or severe heart disorder; concomitant use of metoclopramide; scheduled regional or spinal anesthesia; brain damage, liver disorders, renal insufficiency, pheochromocytoma and blood dyscrasias.
Concerns related to adverse effects:
• Anticholinergic effects: May cause anticholinergic effects (constipation, xerostomia, blurred vision, urinary retention); use with caution in patients with decreased GI motility, paralytic ileus, urinary retention, BPH, xerostomia, glaucoma, or visual problems. Relative to other antipsychotics, loxapine has a low potency of cholinergic blockade (Richelson 1999).
• Blood dyscrasias: Leukopenia, neutropenia, and agranulocytosis (sometimes fatal) have been reported in clinical trials and postmarketing reports with antipsychotic use; presence of risk factors (eg, preexisting low WBC or history of drug-induced leuko-/neutropenia) should prompt periodic blood count assessment. Discontinue therapy at first signs of blood dyscrasias or if absolute neutrophil count <1,000/mm3.
• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks that require mental alertness (eg, operating machinery, driving). Sedation can also mask signs of bronchospasm.
• Esophageal dysmotility/aspiration: Antipsychotic use has been associated with esophageal dysmotility and aspiration; risk increases with age. Use with caution in patients at risk for aspiration pneumonia (ie, Alzheimer disease), particularly in patients >75 years (Herzig 2017; Maddalena 2004).
• Extrapyramidal symptoms: May cause extrapyramidal symptoms (EPS), including pseudoparkinsonism, acute dystonic reactions, akathisia, and tardive dyskinesia. Risk of dystonia (and possibly other EPS) may be greater with increased doses, use of conventional antipsychotics, males, and younger patients. Factors associated with greater vulnerability to tardive dyskinesia include older in age, female gender combined with postmenopausal status, Parkinson disease, pseudoparkinsonism symptoms, affective disorders (particularly major depressive disorder), concurrent medical diseases such as diabetes, previous brain damage, alcoholism, poor treatment response, and use of high doses of antipsychotics (APA [Keepers 2020]; Soares-Weiser 2007). Consider therapy discontinuation with signs/symptoms of tardive dyskinesia. Increased incidence of EPS has been observed with IM administration compared to oral administration.
• Falls: May increase the risk for falls due to somnolence, orthostatic hypotension, and motor or sensory instability.
• Hyperprolactinemia: Antipsychotic use has been associated with increased prolactin levels; clinical significance of hyperprolactinemia in patients with breast cancer or other prolactin-dependent tumors is unknown (APA [Keepers 2020]; Pollack 1993; Wang 2002).
• Hypotension: May cause hypotension, orthostatic hypotension, and syncope; use with caution in patients at risk of this effect or in those who would not tolerate transient hypotensive episodes (cerebrovascular disease, cardiovascular disease, dehydration, hypovolemia, or concurrent medication use that may predispose to hypotension/bradycardia).
• Neuroleptic malignant syndrome (NMS): NMS has been associated with use of antipsychotic agents; monitor for hyperpyrexia, mental status changes, fever, muscle rigidity, and/or autonomic instability. Discontinue treatment immediately with onset of NMS; recurrence has been reported in patients rechallenged with antipsychotic therapy.
• Ocular effects: Antipsychotic use has been associated with pigmentary retinopathy, and lenticular and corneal deposits, particularly with prolonged therapy (Oshika 1995).
• Temperature regulation: Antipsychotic use has been associated with impaired core body temperature regulation; caution with strenuous exercise, heat exposure, dehydration, and concomitant medication possessing anticholinergic effects (Kerwin 2004; Kwok 2005; Martinez 2002).
Disease-related concerns:
• Cardiovascular disease: Use with caution in patients with cardiovascular disease.
• Dementia: Most deaths in elderly patients with dementia-related psychosis treated with antipsychotics appeared to be either cardiovascular (eg, heart failure, sudden death) or infectious (eg, pneumonia) in nature. Use with caution in patients with Lewy body dementia or Parkinson disease dementia due to greater risk of adverse effects, increased sensitivity to extrapyramidal effects, and association with irreversible cognitive decompensation or death. The APA recommends giving preference to second generation antipsychotics over first generation antipsychotics in elderly patients with dementia-related psychosis due to a potentially greater risk of harm relative to second generation antipsychotics (APA [Reus 2016]). Loxapine is not approved for the treatment of dementia-related psychosis.
• 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.
Other warnings/precautions:
• Discontinuation of therapy: When discontinuing antipsychotic therapy, gradually taper antipsychotics to avoid physical withdrawal symptoms and rebound symptoms (APA [Keepers 2020]; WFSBP [Hasan 2012]). Withdrawal symptoms may include agitation, alternating feelings of warmth and cold, anxiety, diaphoresis, dyskinesia, GI symptoms, insomnia, irritability, myalgia, paresthesia, psychosis, restlessness, rhinorrhea, tremor, and vertigo (Lambert 2007; Moncrieff 2020). The risk of withdrawal symptoms is highest following abrupt discontinuation of highly anticholinergic or dopaminergic antipsychotics (Cerovecki 2013). Patients with chronic symptoms, repeated relapses, and clear diagnostic features of schizophrenia are at risk for poor outcomes if medications are discontinued (APA [Keepers 2020]).
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Aerosol Powder Breath Activated, Inhalation:
Adasuve: 10 mg (1 ea)
Aerosol Powder Breath Activated, Inhalation [preservative free]:
Adasuve: 10 mg (1 ea [DSC])
Capsule, Oral:
Generic: 5 mg, 10 mg, 25 mg, 50 mg
May be product dependent
Aerosol powder (Adasuve Inhalation)
10 mg (per each): $180.00
Capsules (Loxapine Succinate Oral)
5 mg (per each): $0.79 - $0.99
10 mg (per each): $1.05 - $1.28
25 mg (per each): $1.58 - $1.92
50 mg (per each): $2.20 - $2.57
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.
Solution, Intramuscular:
Loxapac: 50 mg/mL (1 mL) [contains polysorbate 80, propylene glycol]
Tablet, Oral:
Xylac: 2.5 mg, 10 mg
Xylac: 25 mg [contains fd&c red #40(allura red ac)aluminum lake]
Generic: 5 mg, 10 mg, 25 mg, 50 mg
Inhalation: Must be administered only by a health care professional. Instruct patient to exhale fully. Use inhaler on inspiration and instruct patient to hold breath as long as possible, up to 10 seconds. Check that the green light turns off indicating the dose has been delivered. If the light remains on after the patient inhales, the full dose was not delivered. Repeat inhalation up to 2 additional times. If green light still does not turn off, discard inhaler and use a new one. Inhaler may produce a flash of light and clicking sound, and become warm with use; this is normal. Discard after one use.
Oral solution [Canadian product]: Mix prior to administration.
Solution for injection [Canadian product] is administered by IM injection. Do not administer IV
Adasuve: An FDA-approved patient medication guide, which is available with the product information and at https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/022549s010lbl.pdf#page=28, must be dispensed with this medication.
Schizophrenia: Oral: Treatment of schizophrenia.
Agitation associated with schizophrenia or bipolar I disorder: IM [Canadian product]; Inhalation: Acute treatment of agitation associated with schizophrenia or bipolar I disorder in adults. Note: As part of the Adasuve REMS program to mitigate the risk of bronchospasm, loxapine inhalation must be administered only in a certified health care setting.
Loxitane [DSC] may be confused with FLUoxetine, Lexapro, Soriatane.
Beers Criteria: Antipsychotics are identified in the Beers Criteria as potentially inappropriate medications to be avoided in patients 65 years and older due to an increased risk of stroke and a greater rate of cognitive decline and mortality in patients with dementia. Evidence also suggests there may be an increased risk of mortality with use independent of dementia. Avoid antipsychotics for behavioral problems associated with dementia or delirium unless alternative nonpharmacologic therapies have failed and patient may harm self or others. In addition, antipsychotics should be used with caution in older adults 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. Use of antipsychotics may be appropriate for labeled indications including schizophrenia, bipolar disorder, Parkinson disease psychosis, adjunctive therapy in major depressive disorder, or for short-term use as an antiemetic (Beers Criteria [AGS 2023]).
Loxitane [US] may be confused with Lexotan which is a brand name for bromazepam [multiple international markets].
Substrate of CYP1A2 (Minor), CYP2D6 (Minor), 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.
Agents to Treat Airway Disease: May increase adverse/toxic effects of Loxapine. More specifically, the use of Agents to Treat Airway Disease is likely a marker of patients who are likely at a greater risk for experiencing significant bronchospasm from use of inhaled loxapine. Management: This is specific to the Adasuve brand of loxapine, which is an inhaled formulation. This does not apply to non-inhaled formulations of loxapine. Risk X: Avoid
Agents With Seizure Threshold Lowering Potential: May increase adverse/toxic effects of Loxapine. Specifically, the risk of seizures may be increased. Risk C: Monitor
Alizapride: May increase CNS depressant effects of CNS Depressants. 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 adverse/toxic effects of Antipsychotic Agents. Specifically, the risk of neuroleptic malignant syndrome or increased QTc interval may be increased. Risk C: Monitor
Amisulpride (Oral): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Anti-Parkinson Agents (Dopamine Agonist): Antipsychotic Agents (First Generation [Typical]) may decrease therapeutic effects of Anti-Parkinson Agents (Dopamine Agonist). Management: Avoid concomitant therapy if possible. If antipsychotic use is necessary, consider using atypical antipsychotics such as clozapine, quetiapine, or ziprasidone at lower initial doses, or a non-dopamine antagonist (eg, pimavanserin). Risk D: Consider Therapy Modification
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
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
Azelastine (Nasal): May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
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
Benzgalantamine-Galantamine: May increase neurotoxic (central) effects of Antipsychotic Agents. 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: May increase adverse/toxic effects of Antipsychotic Agents. Specifically, tardive dyskinesia symptoms may be potentiated. 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 Antipsychotic Agents. Risk X: Avoid
Bromperidol: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
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: May increase neuroexcitatory and/or seizure-potentiating effects of Agents With Seizure Threshold Lowering Potential. Risk C: Monitor
BusPIRone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Cabergoline: May decrease therapeutic effects of Antipsychotic Agents. Risk X: Avoid
Cannabinoid-Containing Products: CNS Depressants may increase CNS depressant effects of Cannabinoid-Containing Products. Risk C: Monitor
CarBAMazepine: Loxapine may increase active metabolite exposure of CarBAMazepine. Specifically, concentrations of carbamazepine epoxide (CBZE) may be increased. 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
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
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
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: Antipsychotic Agents may increase adverse/toxic effects of Dexmethylphenidate-Methylphenidate. Dexmethylphenidate-Methylphenidate may increase adverse/toxic effects of Antipsychotic Agents. Specifically, the risk of extrapyramidal symptoms may be increased when these agents are combined. Risk C: Monitor
Difelikefalin: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Dihydralazine: CNS Depressants may increase hypotensive effects of Dihydralazine. Risk C: Monitor
Dimethindene (Topical): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Donepezil: May increase neurotoxic (central) effects of Antipsychotic Agents. Risk C: Monitor
Dothiepin: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
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
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
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
Guanethidine: Antipsychotic Agents may decrease therapeutic effects of Guanethidine. Risk C: Monitor
Huperzine A: May increase neurotoxic (central) effects of Antipsychotic Agents. 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
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
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
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
Lithium: May increase neurotoxic effects of Antipsychotic Agents. Lithium may decrease serum concentration of Antipsychotic Agents. Specifically noted with chlorpromazine. Risk C: Monitor
Lofexidine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
LORazepam: Loxapine may increase adverse/toxic effects of LORazepam. Specifically, prolonged stupor, respiratory depression, and/or hypotension. Risk C: Monitor
Magnesium Sulfate: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Mequitazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Metergoline: Antipsychotic Agents may decrease therapeutic effects of Metergoline. Metergoline may decrease therapeutic effects of Antipsychotic Agents. 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
Metoclopramide: May increase adverse/toxic effects of Antipsychotic Agents. Risk X: Avoid
MetyroSINE: CNS Depressants may increase sedative effects of MetyroSINE. Risk C: Monitor
MetyroSINE: May increase adverse/toxic effects of Antipsychotic Agents. Specifically, the risk for extrapyramidal symptoms and excessive sedation may be increased. Risk C: Monitor
Minocycline (Systemic): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Moxonidine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Nabilone: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Noscapine: CNS Depressants may increase adverse/toxic effects of Noscapine. Risk X: Avoid
Olopatadine (Nasal): May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
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 CNS depressant effects of CNS Depressants. Risk C: Monitor
Orphenadrine: CNS Depressants may increase CNS depressant effects of Orphenadrine. Risk X: Avoid
Oxomemazine: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
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
Paraldehyde: CNS Depressants may increase CNS depressant effects of Paraldehyde. Risk X: Avoid
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 Seizure Threshold Lowering Potential may increase adverse/toxic effects of Perphenazine. 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: Antipsychotic Agents may decrease therapeutic effects of Piribedil. Piribedil may decrease therapeutic effects of Antipsychotic Agents. Management: Use of piribedil with antiemetic neuroleptics is contraindicated, and use with antipsychotic neuroleptics, except for clozapine, is not recommended. Risk X: Avoid
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
Procarbazine: May increase CNS depressant effects of CNS Depressants. 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
Quinagolide: Antipsychotic Agents may decrease therapeutic effects of Quinagolide. Risk C: Monitor
Rilmenidine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Rivastigmine: May increase neurotoxic (central) effects of Antipsychotic Agents. Risk C: Monitor
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
Serotonergic Agents (High Risk): May increase adverse/toxic effects of Antipsychotic Agents. Specifically, serotonergic agents may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotic Agents may increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. 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
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
Sulpiride: Antipsychotic Agents may increase adverse/toxic effects of Sulpiride. Risk X: Avoid
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
Thalidomide: CNS Depressants may increase CNS depressant effects of Thalidomide. Risk X: Avoid
Triptorelin: Hyperprolactinemic Agents may decrease therapeutic effects of Triptorelin. Risk X: Avoid
Valerian: May increase CNS depressant effects of CNS Depressants. 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
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
Antipsychotic use during the third trimester of pregnancy has a risk for abnormal muscle movements (extrapyramidal symptoms [EPS]) and withdrawal symptoms in newborns following delivery. Symptoms in the newborn may include agitation, feeding disorder, hypertonia, hypotonia, respiratory distress, somnolence, and tremor; these effects may be self-limiting or require hospitalization.
Data collection to monitor pregnancy and infant outcomes following exposure to loxapine is ongoing. Health care providers are encouraged to enroll patients exposed to loxapine during pregnancy in the National Pregnancy Registry for Atypical Antipsychotics (866-961-2388 or http://womensmentalhealth.org/clinical-and-researchprograms/pregnancyregistry/).
It is not known if loxapine is present in breast milk.
According to the manufacturer, the decision to breastfeed during therapy should consider the risk of infant exposure, the benefits of breastfeeding to the infant, and the benefits of treatment to the mother.
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Frequency of Antipsychotic Monitoring in Loxapinea,b | ||
|---|---|---|
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Monitoring parameter |
Frequency of monitoring |
Comments |
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a For all monitoring parameters, it is appropriate for check at baseline and when clinically relevant (based on symptoms or suspected adverse reactions) in addition to the timeline. | ||
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b ADA 2004; APA [Keepers 2020]; Landi 2005; Seppala 2018; manufacturer's labeling. | ||
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c Risk factors for extrapyramidal symptoms (EPS) include prior history of EPS, high doses of antipsychotics, young age (children and adolescents at higher risk than adults), and dopaminergic affinity of individual antipsychotic. | ||
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d Risk factors for tardive dyskinesia include age >55 years; females; White or African ethnicity; presence of a mood disorder, intellectual disability, or CNS injury; and past or current EPS. | ||
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Adherence |
Every visit |
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Blood chemistries (electrolytes, renal function, liver function, TSH) |
As clinically indicated |
|
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CBC |
As clinically indicated |
Check frequently during the first few months of therapy in patients with preexisting low WBC or history of drug-induced leukopenia/neutropenia. |
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Extrapyramidal symptoms |
Every visit; 4 weeks after initiation and dose change; annually. Use a formalized rating scale at least annually or every 6 months if high risk.c |
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Fall risk |
As clinically indicated |
Evaluate regularly in patients ≥60 years of age. |
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Fasting plasma glucose/HbA1c |
4 months after initiation; annually |
Check more frequently than annually if abnormal. Follow diabetes guidelines. |
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Lipid panel |
4 months after initiation; annually |
Check more frequently than annually if abnormal. Follow lipid guidelines. |
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Mental status and alertness |
Every visit |
|
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Metabolic syndrome history |
Annually |
Evaluate for personal and family history of obesity, diabetes, dyslipidemia, hypertension, or cardiovascular disease. |
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Ocular exam |
As clinically indicated |
Particularly important for those taking thioridazine or chlorpromazine, or those with diabetes and other conditions that impact sight. |
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Prolactin |
Ask about symptoms at every visit until dose is stable. Check prolactin level if symptoms are reported. |
Hyperprolactinemia symptoms: Changes in menstruation, libido, gynecomastia, development of galactorrhea, and erectile and ejaculatory function. |
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Tardive dyskinesia |
Every visit; annually. Use a formalized rating scale at least annually or every 6 months if high risk.d |
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Vital signs (BP, orthostatics, temperature, pulse, signs of infection) |
As clinically indicated |
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Weight/Height/BMI |
Every visit for first 6 months, then quarterly |
Consider monitoring waist circumference at baseline and annually, especially in patients with or at risk for metabolic syndrome. Consider changing antipsychotic if BMI increases by ≥1 unit. |
Additional monitoring for inhaler: Monitor for signs and symptoms of bronchospasm for at least 1 hour after administration.
Timing of serum samples: Draw trough just before next dose (Hiemke 2018).
Therapeutic reference range: 5 to 10 ng/mL (SI: 15.25 to 30.5 nmol/L) (Hiemke 2018). Note: Dosing should be based on therapeutic response as opposed to serum concentrations; however, therapeutic drug monitoring can be used to confirm adherence (APA [Keepers 2020]).
Laboratory alert level: 20 ng/mL (SI: 61 nmol/L) (Hiemke 2018).
Loxapine is a dibenzoxazepine antipsychotic that blocks postsynaptic mesolimbic D1 and D2 receptors in the brain, and also possesses serotonin 5-HT2-blocking activity.
Onset of action:
Agitation:
Inhalation: Initial effects within 10 minutes (Citrome 2012)
Oral, IM [Canadian product]: Within 30 minutes; Peak effect: 1.5 to 3 hours
Schizophrenia: Oral: Initial effects may be observed within 1 to 2 weeks of treatment with continued improvements through 4 to 6 weeks (Agid 2003; Levine 2010).
Duration: Oral, IM: ~12 hours
Absorption: Oral, inhalation, IM: Rapid and complete
Protein binding: Inhalation: ~97%
Metabolism: Hepatic demethylation and hydroxylation to produce active metabolites, desmethylloxapine (aka, amoxapine), 7-hydroxyamoxapine (7-OH-amoxapine), 7-hydroxyloxapine (7-OH-loxapine), 8-hydroxyamoxapine (8-OH-amoxapine) and 8-hydroxyloxapine (8-OH-loxapine) (Burch 1983; Cheung 1991; Fulton 1982; Simpson 1978); metabolites undergo conjugation to form glucuronides.
Bioavailability: Inhalation: 91% (de Berardis 2017)
Half-life elimination: Oral: Biphasic: Initial: 5 hours; Terminal: 19 hours; Inhalation: 6 to 8 hours
Excretion: Urine (as metabolites); feces (as metabolites)
Toxicokinetics:
Absorption: In overdose, the anticholinergic effects of tricyclic antidepressants (eg, loxapine) may result in slowed gastric emptying and subsequent prolonged absorption from the small intestine (Jarvis 1991). In addition, saturation of first-pass metabolism of tricyclic antidepressants in overdose may increase the bioavailability (Rosenberg 1981).
Single-dose activated charcoal: Minimal effect on absorption (Bosse 1995; Crome 1983; Hultén 1988).
Distribution: Protein binding: Acidemia (metabolic or respiratory acidosis) secondary to tricyclic antidepressant (eg, loxapine) toxicity may result in decreased protein binding further contributing to higher plasma concentrations (Jarvis 1991).
Metabolism: Loxapine is metabolized to active metabolites (amoxapine; 7-OH-amoxapine; 7-OH-loxapine; 8-OH-amoxapine; 8-OH-loxapine) (Burch 1983; Cheung 1991; Fulton 1982; Simpson 1978) which may contribute to toxicity in overdose.
Elimination: Enterohepatic recirculation of both loxapine and its active metabolites may result in prolonged elimination following overdose (Jarvis 1991).
Multidose activated charcoal: Reduced the half-life of other tricyclic antidepressants (ie, amitriptyline) in overdose by more than half (Swartz 1984).
Extracorporeal elimination: Minimal effect on elimination of tricyclic antidepressants (Yates 2014).
