Use methohexital only in hospital or ambulatory care settings that provide for continuous monitoring of respiratory (eg, pulse oximetry) and cardiac function. Ensure immediate availability of resuscitative drugs and age- and size-appropriate equipment for bag/valve/mask ventilation and intubation and personnel trained in their use and skilled in airway management. For deeply sedated patients, a designated individual other than the practitioner performing the procedure should be present to continuously monitor the patient.
General anesthesia: IV: Usual dosing range: 1 to 1.5 mg/kg for induction; titrate to response and tolerability.
Procedural sedation (off-label dose): IV: Usual dosing range: 0.75 to 1 mg/kg; redose with 0.5 mg/kg every 2 to 5 minutes based on response and tolerability (Ref).
Wada test (off-label use): Intracarotid (off-label route): 3 to 4 mg over 3 seconds; a second dose may be administered at 2 mg over 2 seconds based on response and tolerability (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provided in the manufacturer's labeling; use with caution.
There are no dosage adjustments provided in the manufacturer's labeling. However, adjustment may be necessary due to hepatic metabolism. Use with caution.
Refer to adult dosing. Reduce dose or administer at the low end of the dosage range.
(For additional information see "Methohexital: Pediatric drug information")
Note: Doses must be titrated to effect.
Induction :
IM: Infants and Children: 5% (50 mg/mL) solution: 6.6 to 10 mg/kg/dose
IV: Limited data available: Infants, Children, and Adolescents: 1% (10 mg/mL) solution: 1 to 2.5 mg/kg/dose; usual adult dose is 70 mg (ie, 1 mg/kg); if patient is premedicated, dose should be decreased (Ref)
Rectal: Infants and Children: 1% (10 mg/mL) solution or 10% (100 mg/mL) solution: 25 mg/kg/dose; reported maximum dose: 500 mg/dose (Ref)
Procedural sedation:
IM: Infants and Children: 5% (50 mg/mL) solution: 10 mg/kg/dose (Ref). Note: Some experts do not suggest routine use due to slower onset (Ref)
IV: Limited data available: Infants, Children, and Adolescents: 1% (10 mg/mL) solution: Initial: 0.5 to 1 mg/kg/dose administer immediately prior to procedure; titrate additional doses to achieve level of sedation as needed in increments of 0.5 mg/kg to a maximum total dose: 2 mg/kg total. In the prospective phase of a trial including 20 infants and children (mean age: 26 ± 17 months) undergoing CT scans, a mean dose of 1 ± 0.5 mg/kg/dose was reported (Ref)
Rectal: Infants and Children: 10% (100 mg/mL) solution: Usual: 25 mg/kg/dose; range: 20 to 35 mg/kg/dose; maximum dose: 500 mg/dose; administer 5 to 15 minutes prior to procedure (Ref)
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provided in the manufacturer's labeling; use with caution.
All patients: There are no dosage adjustments provided in the manufacturer's labeling. However, adjustment may be necessary due to hepatic metabolism. Use with caution.
The following adverse drug reactions are derived from product labeling unless otherwise specified.
Frequency not defined:
Cardiovascular: Circulatory depression, circulatory shock, tachycardia
Dermatologic: Erythema of skin, pruritus, urticaria
Gastrointestinal: Abdominal pain, salivation
Hepatic: Abnormal hepatic function tests
Local: Injection-site reaction (injury to nerves adjacent to injection-site)
Nervous system: Headache, postanesthetic shivering
Neuromuscular & skeletal: Muscle twitching
Respiratory: Bronchospasm, dyspnea, rhinitis
Postmarketing:
Cardiovascular: Hypotension (Whitwam 1978), thrombophlebitis (Whitwam 1978)
Gastrointestinal: Hiccups (Whitwam 1978), nausea (Whitwam 1978), vomiting (Whitwam 1978)
Hypersensitivity: Anaphylaxis, hypersensitivity reaction (Whitwam 1978)
Local: Pain at injection site (Whitwam 1978)
Nervous system: Seizure (Rockoff 1981), tremor (Whitwam 1978)
Neuromuscular & skeletal: Laryngospasm (Whitwam 1978), muscle movements (Whitwam 1978)
Respiratory: Apnea (Whitwam 1978, Yemen 1991), cough (Whitwam 1978), respiratory depression (Whitwam 1978)
Hypersensitivity to methohexital or any component of the formulation; porphyria (latent or manifest); patients in whom general anesthesia is contraindicated
Concerns related to adverse effects:
• 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 or driving); however, the duration of action is <10 minutes when used for procedural sedation (Bahn 2005).
• Hypotension/tachycardia: May cause temporary hypotension and tachycardia; use with caution in hemodynamically unstable patients (hypotension or shock) or severe hypertension.
Disease-related concerns:
• Anemia: Use with caution in patients with severe anemia; respiratory depression may occur leading to further inadequate tissue oxygenation.
• Cardiovascular disease: Use with caution in patients with cardiovascular disease including heart failure; consider monitoring cardiac function. Methohexital may enhance preexisting circulatory depression, severe cardiovascular instability, or a shock-like condition; consider using another induction agent in these patients.
• Hepatic impairment: Use with caution in patients with hepatic impairment; may prolong or potentiate hypnotic effect.
• Obesity: Use with caution in patients with extreme obesity.
• Pulmonary disease: May cause respiratory depression; use with caution in patients with pulmonary disease. Use with caution in patients with asthma and chronic obstructive pulmonary disease. Use with extreme caution in patients with ongoing status asthmaticus; hiccups, coughing, laryngospasm, and muscle twitching have occurred impairing ventilation.
• Renal impairment: Use with caution in patients with renal impairment; may prolong or potentiate hypnotic effect.
• Seizure disorder: Use with caution in patients with a history of seizure disorder.
Special populations:
• Debilitated patients: Use with caution in debilitated patients.
• Older adult: Use with caution in the elderly.
• Pediatric neurotoxicity: In pediatric and neonatal patients <3 years and patients in third trimester of pregnancy (ie, times of rapid brain growth and synaptogenesis), the repeated or lengthy exposure to sedatives or anesthetics during surgery/procedures may have detrimental effects on child or fetal brain development and may contribute to various cognitive and behavioral problems. Epidemiological studies in humans have reported various cognitive and behavioral problems including neurodevelopmental delay (and related diagnoses), learning disabilities, and ADHD. Human clinical data suggest that single, relatively short exposures are not likely to have similar negative effects. No specific anesthetic/sedative has been found to be safer. For elective procedures, risk vs benefits should be evaluated and discussed with parents/caregivers/patients; critical surgeries should not be delayed (FDA 2016).
Other warnings/precautions:
• Appropriate administration: [US Boxed Warning]: Should only be administered in hospitals or ambulatory care settings with continuous monitoring of respiratory (eg, pulse oximetry) and cardiac function. Immediate availability of resuscitative drugs and age- and size-appropriate intubation equipment and trained personnel experienced in handling their use should be immediately available and personnel trained in their use and skilled in airway management should be assured. For deeply sedated patients, a designated individual other than the healthcare provider performing the procedure should be present to continuously monitor the patient. Maintenance of a patent airway and adequacy of ventilation must be ensured during use. Laryngospasm is common during induction with all barbiturates.
• Cumulative effect: Repeated dosing or continuous infusions may cause cumulative effects.
• Intravenous (IV) administration: Prior to IV administration, ensure patient has adequate IV access; extravasation or intra-arterial injection causes necrosis.
In pediatric and neonatal patients <3 years of age and patients in third trimester of pregnancy (ie, times of rapid brain growth and synaptogenesis), the repeated or lengthy exposure to sedatives or anesthetics during surgery/procedures may have detrimental effects on the child's or fetus' brain development and may contribute to various cognitive and behavioral problems; the FDA is requiring warnings be included in the manufacturer's labeling for all general anesthetic/sedative drugs. Multiple animal species studies have shown adverse effects on brain maturation; in juvenile animals, drugs that potentiate GABA activity and/or block NMDA receptors for >3 hours demonstrated widespread neuronal and oligodendrocyte cell loss along with alteration in synaptic morphology and neurogenesis. Epidemiological studies in humans have reported various cognitive and behavioral problems including neurodevelopmental delay (and related diagnoses), learning disabilities, and ADHD. Human clinical data suggest that single, relatively short exposures are not likely to have similar negative effects. Further studies are needed to fully characterize findings and ensure that these findings are not related to underlying conditions or the procedure itself. No specific anesthetic/sedative has been found to be safer. For elective procedures, risk vs benefits should be evaluated and discussed with parents/caregivers/patients; critical surgeries should not be delayed (FDA 2016).
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Solution Reconstituted, Injection, as sodium:
Generic: 500 mg (1 ea)
Solution Reconstituted, Injection, as sodium [preservative free]:
Brevital Sodium: 500 mg (1 ea)
Yes
Solution (reconstituted) (Brevital Sodium Injection)
500 mg (per each): $133.84
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C-IV
IM administration: Use 5% (50 mg/mL) solution.
IV: Dilute to a maximum concentration of 1% prior to IV use.
Induction of anesthesia: 1% (10 mg/mL) solution is administered IV at a rate of ~1 mL/5 seconds or ~2 mg/second.
Intracarotid (off-label route): Wada test (off-label use): 0.1% (1 mg/mL) solution has been used; administer dose at a rate of 1 mg/second into the internal carotid artery (Ref).
Rectal administration: Use 1% (10 mg/mL) solution; 10% (100 mg/mL) solution has also been used (Ref).
Parenteral:
IM: Use 5% solution (50 mg/mL)
IV:
Bolus: For induction, infuse a 1% solution (10 mg/mL) at a rate of ~1 mL/5 seconds (ie, ~2 mg/second, or 12 mL/minute [120 mg/minute] depending upon pump setting)
Continuous IV infusion: Adults: Use a 0.2% solution (2 mg/mL)
Rectal: Use a 1% solution (10 mg/mL); a 10% solution (100 mg/mL) has also been given rectally (Ref)
General anesthesia: Induction of anesthesia prior to the use of other general anesthetic agents; to supplement other anesthetic agents for longer surgical procedures.
Procedural sedation: Short surgical, diagnostic, or therapeutic procedures associated with minimal painful stimuli.
Rapid sequence intubation, outside the operating room; Wada test
Brevital may be confused with Brevibloc
The Institute for Safe Medication Practices (ISMP) includes this medication among its list of drug classes (anesthetic agent, general, inhaled and IV) which have a heightened risk of causing significant patient harm when used in error (High-Alert Medications in Acute Care Settings).
None known.
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.
Acrivastine: May increase CNS depressant effects of CNS Depressants. 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
Amisulpride (Oral): May increase CNS depressant effects of CNS Depressants. 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: May increase CNS depressant effects of CNS Depressants. 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
Blood Pressure Lowering Agents: Barbiturates may increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Brexanolone: CNS Depressants may increase CNS depressant effects of Brexanolone. Risk C: Monitor
Brimonidine (Topical): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Bromopride: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
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
BusPIRone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Cannabinoid-Containing Products: CNS Depressants may increase CNS depressant effects of Cannabinoid-Containing Products. 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 adverse/toxic effects of CNS Depressants. Risk C: Monitor
Dantrolene: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
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
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 (Topical): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Doxycycline: Barbiturates may decrease serum concentration of Doxycycline. Risk C: Monitor
Doxylamine: CNS Depressants may increase CNS depressant effects of Doxylamine. 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
Esketamine (Nasal): 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
Hemin: Barbiturates may decrease therapeutic effects of Hemin. Risk X: Avoid
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
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
Lisuride: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Lofexidine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
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
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: 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: Barbiturates may increase nephrotoxic effects of Methoxyflurane. Barbiturates may increase metabolism of Methoxyflurane. Risk X: Avoid
Metoclopramide: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
MetyroSINE: CNS Depressants may increase sedative effects of MetyroSINE. Risk C: Monitor
Mianserin: May increase CNS depressant effects of Barbiturates. Mianserin may decrease therapeutic effects of Barbiturates. Barbiturates may decrease serum concentration of Mianserin. Risk X: Avoid
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
Multivitamins/Minerals (with ADEK, Folate, Iron): May decrease serum concentration of Barbiturates. Risk C: Monitor
Nabilone: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Nalfurafine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
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
Oxybate Salt Products: Barbiturates may increase CNS depressant effects of Oxybate Salt Products. 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
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
Perampanel: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Periciazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Pipamperone: May increase adverse/toxic effects of CNS Depressants. Risk C: Monitor
Piribedil: CNS Depressants may increase CNS depressant effects of Piribedil. Risk C: Monitor
Pizotifen: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Pramipexole: CNS Depressants may increase sedative effects of Pramipexole. Risk C: Monitor
Procarbazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Rilmenidine: May increase CNS depressant effects of CNS Depressants. 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
ROPINIRole: CNS Depressants may increase sedative effects of ROPINIRole. Risk C: Monitor
Rotigotine: CNS Depressants may increase sedative effects of Rotigotine. 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
Thalidomide: CNS Depressants may increase CNS depressant effects of Thalidomide. Risk X: Avoid
Theophylline Derivatives: Barbiturates may decrease serum concentration of Theophylline Derivatives. Risk C: Monitor
Tricyclic Antidepressants: 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
Trimeprazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Valerian: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Valproic Acid and Derivatives: May increase CNS depressant effects of Barbiturates. Valproic Acid and Derivatives may increase serum concentration of Barbiturates. Barbiturates may decrease serum concentration of Valproic Acid and Derivatives. Risk C: Monitor
Vitamin K Antagonists: Barbiturates may increase metabolism of Vitamin K Antagonists. Management: Monitor INR more closely. Anticoagulant dose increases of 30% to 60% may be needed after a barbiturate is initiated or given at an increased dose. Anticoagulant dose decreases may be needed following barbiturate discontinuation or dose reduction. Risk D: Consider Therapy Modification
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
Methohexital crosses the placenta.
Based on animal data, repeated or prolonged use of general anesthetic and sedation medications that block N-methyl-D-aspartate (NMDA) receptors and/or potentiate gamma-aminobutyric acid (GABA) activity may affect brain development. Evaluate benefits and potential risks of fetal exposure to methohexital when duration of surgery is expected to be >3 hours (Olutoye 2018).
Use of methohexital in obstetric anesthesia has been described (Holdcroft 1974; Lee 1966; Verma 1985). However, other agents are more commonly used (ACOG 209 2019; Devroe 2015).
The ACOG recommends that pregnant women should not be denied medically necessary surgery, regardless of trimester. If the procedure is elective, it should be delayed until after delivery (ACOG 775 2019).
Methohexital is present in breast milk (Borgatta 1997).
Breast milk concentrations of methohexital were highest ~1 hour following induction of anesthesia in nine women undergoing sterilization ≥1 months postpartum. Methohexital was not measurable in the maternal breast milk of four women 8 to 10 hours after the dose. None of the women had detectable milk or serum concentrations ≥24 hours after the dose (Borgatta 1997).
The manufacturer recommends that caution be exercised when administering methohexital to breastfeeding women. The Academy of Breast Feeding Medicine recommends postponing elective surgery until milk supply and breastfeeding are established. Milk should be expressed ahead of surgery when possible. In general, when the child is healthy and full term, breastfeeding may resume, or milk may be expressed once the mother is awake and in recovery. For children who are at risk for apnea, hypotension, or hypotonia, milk may be saved for later use when the child is at lower risk (ABM [Reece-Stremtan 2017]).
Respiratory (eg, pulse oximetry and capnography), cardiovascular (eg, cardiac monitoring, BP, heart rate), CNS status (when used for anesthesia and/or procedures, monitor sedation level).
Methohexital is an ultra short-acting IV barbiturate anesthetic. Barbiturates depress the sensory cortex, decrease motor activity, and alter cerebellar function producing drowsiness, sedation, and hypnosis.
Onset of action: IV: Immediate; IM (pediatrics): 2 to 10 minutes; Rectal (pediatrics): 5 to 15 minutes
Duration: Single dose:
IM: 1 to 1.5 hours
IV: Time to clinical recovery (ie, awake time, sitting and standing steadily, duration of amnesia): 5 to 15 minutes (psychomotor impairment may continue for up to 8 hours) (Barash 2009; Fredman 1994; Korttila 1975)
Rectal (pediatrics): 45 to 60 minutes (Cote 1994)
Metabolism: Hepatic via demethylation and oxidation
Bioavailability: Rectal: 17%
Half-life elimination: 1.6 to 3.9 hours (Ghoneim 1985)
Excretion: Urine