Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
METHOHEXITAL SODIUM vs BREVITAL SODIUM
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Methohexital sodium is a barbiturate that acts as a GABA-A receptor agonist, enhancing chloride conductance and causing neuronal hyperpolarization. It produces rapid sedation and anesthesia by depressing the central nervous system.
Brevital sodium (methohexital) is a barbiturate that acts as a GABA-A receptor agonist, enhancing chloride ion influx and hyperpolarizing neurons, leading to rapid sedation and anesthesia.
Induction of anesthesia (FDA-approved),Maintenance of anesthesia (as an adjunct) (FDA-approved),Procedural sedation (off-label),Treatment of refractory status epilepticus (off-label)
Induction and maintenance of general anesthesia,Adjunct to regional anesthesia,Short-duration surgical procedures
Induction of anesthesia: 1-1.5 mg/kg IV bolus over 15-30 seconds. Maintenance: intermittent IV boluses of 20-40 mg every 4-7 minutes as needed.
Induction of anesthesia: 1-1.5 mg/kg IV bolus over 15 seconds; maintenance: 0.5-1 mg/kg IV bolus as needed or 50-150 mcg/kg/min IV infusion.
Terminal elimination half-life is 1.6–4.8 hours (mean ~3.9 hours) in adults. Context: Rapid redistribution shortens clinical duration; elimination half-life is longer in elderly and hepatic impairment.
Terminal elimination half-life: 3–6 hours (mean ~4 hours); prolonged in hepatic impairment, obesity, or with repeated dosing due to redistribution.
Primarily hepatic metabolism via CYP2B6 and other microsomal enzymes; undergoes oxidation and glucuronidation. Active metabolites are minimally important.
Hepatic metabolism primarily by CYP2C9 and CYP3A4 to inactive metabolites; less than 1% excreted unchanged in urine.
Renal: <1% unchanged; hepatic metabolism followed by renal excretion of metabolites accounts for >95% of elimination. Fecal: negligible (<1%).
Primarily hepatic biotransformation to inactive metabolites (mainly hydroxy-methohexital), with renal excretion of metabolites; less than 1% excreted unchanged in urine. Minor biliary/fecal elimination.
85–90% bound to albumin.
Approximately 70–90% bound to albumin.
2.0–3.0 L/kg; context: High Vd due to extensive tissue distribution, especially to adipose tissue.
Vd: 1.1–2.5 L/kg (mean ~1.5 L/kg). Larger Vd indicates extensive tissue distribution (highly lipophilic), leading to rapid redistribution and short duration after single bolus.
Intramuscular: ~90–100%; Rectal: ~70–80%; Oral: not available (inactive due to first-pass metabolism).
IV: 100%. IM: Not well established; likely >90%. Rectal: Variable, ~50–70% due to first-pass metabolism and incomplete absorption.
No specific dose adjustment required for GFR 30-89 m L/min. For GFR <30 m L/min or dialysis: use with caution; consider reduced dose due to potential prolonged effect.
No dosage adjustment required for GFR ≥10 m L/min; for GFR <10 m L/min, reduce dose by 50%.
Child-Pugh Class A: no adjustment. Child-Pugh Class B: reduce dose by 25-50%. Child-Pugh Class C: use alternative agent or reduce dose by 50% with careful titration.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: reduce dose by 75% or consider alternative.
Induction: 1-2 mg/kg IV bolus. Maintenance: 0.5-1 mg/kg IV bolus as needed. Maximum single dose: 100 mg.
Induction: 1-2 mg/kg IV; maintenance: 0.5-1 mg/kg IV bolus or 50-150 mcg/kg/min IV infusion. Contraindicated in infants <2 months with stable BSA.
Reduce initial dose by 25-50% (0.5-1 mg/kg IV) and titrate slowly due to increased sensitivity and prolonged recovery.
Reduce induction dose by 50% and administer slowly over 60 seconds; maintenance infusion rates at lower end (50-100 mcg/kg/min).
Risk of respiratory depression and apnea; intravenous administration should be performed only by persons trained in the use of general anesthetics and able to maintain a patent airway and support ventilation. Continuous monitoring of respiratory function is required.
None.
Respiratory depression and apnea,Hypotension and bradycardia,Injection site reactions (thrombophlebitis, necrosis, extravasation),Risk of emergence delirium and postoperative confusion,Laryngospasm and bronchospasm,Accumulation with repeated doses in patients with hepatic or renal impairment
Respiratory depression and apnea may occur; resuscitative equipment must be available,Hypotension and bradycardia possible; use with caution in patients with cardiovascular disease,Extravasation causes tissue necrosis; avoid intra-arterial injection,Seizures may occur in epileptic patients,Rapid injection may cause severe respiratory depression
Hypersensitivity to methohexital or other barbiturates,Acute intermittent porphyria or porphyria variegata,Uncontrolled severe hypotension or shock,Status asthmaticus,Severe respiratory insufficiency,Known or suspected massive drug overdose
Known hypersensitivity to barbiturates,Porphyria (may precipitate acute attacks),Severe respiratory insufficiency,Status asthmaticus,Hypovolemic shock or severe hypotension
No specific food interactions are documented for methohexital sodium. However, it is recommended to avoid heavy meals immediately before anesthesia to reduce risk of aspiration. Grapefruit juice may theoretically increase barbiturate levels by inhibiting CYP3A4, though clinical significance is unclear. Always follow pre-operative fasting instructions.
No specific food interactions are documented for BREVITAL SODIUM. However, patients should avoid heavy meals before anesthesia due to risk of aspiration. Do not consume alcohol or grapefruit juice for 24 hours before and after administration, as they may alter drug metabolism and increase sedation.
Methohexital sodium is a barbiturate anesthetic. Use in the first trimester may be associated with a small increased risk of major malformations based on limited human data; animal studies show developmental toxicity at high doses. In the second and third trimesters, there is a risk of fetal depression and neonatal withdrawal if used chronically near term. Avoid in first trimester if possible; use only if clearly needed.
Teratogenic potential not fully established in humans. In animal studies, methohexital caused fetal resorptions and malformations at maternally toxic doses. First trimester: Avoid unless essential; risk of neural tube defects cannot be excluded. Second trimester: Limited data, but may cause fetal depression if used near delivery. Third trimester: Crosses placenta; may cause neonatal respiratory depression, hypotonia, and prolonged sedation. Use only if clearly needed with lowest effective dose.
Methohexital enters breast milk in low amounts; the infant dose is estimated at <1% of maternal weight-adjusted dose. M/P ratio is approximately 0.5. Due to potential for neonatal sedation and the drug's short half-life, breastfeeding should be avoided for at least 4-6 hours after maternal administration.
Excretion into human milk unknown. M/P ratio not determined. Due to short half-life, minimal transfer expected after a single dose. Caution with repeated doses or prolonged infusion. Monitor infant for sedation, feeding difficulties, or respiratory depression.
Pregnancy may alter pharmacokinetics: increased volume of distribution and clearance may require slightly higher initial doses for induction, but no specific dose adjustment is recommended; titrate to effect. Use lowest effective dose due to potential for fetal depression.
Pregnancy may increase volume of distribution and clearance, potentially requiring higher initial doses, but the induction dose typically unchanged. Reduced doses may be needed in preeclampsia or cesarean section due to enhanced sensitivity. No specific dose adjustment guidelines; titrate to effect with careful monitoring.
METHOHEXITAL SODIUM is an ultra-short-acting barbiturate used for induction of general anesthesia. It has a rapid onset (less than 30 seconds) and short duration (5-10 minutes) due to redistribution. It is highly protein-bound and should be used with caution in patients with hypoalbuminemia. Contraindicated in porphyria. Avoid extravasation as it is a tissue irritant. May cause apnea, laryngospasm, and hypotension. Dose reduction needed in elderly or debilitated patients.
BREVITAL SODIUM (methohexital) is an ultrashort-acting barbiturate used for induction of anesthesia and for short procedures. Due to its rapid onset and brief duration, it requires careful titration. It is contraindicated in patients with porphyria. Extravasation causes tissue necrosis; administer only through a secure IV line. It lowers seizure threshold, but can also be used for electroconvulsive therapy (ECT) to induce seizures. Respiratory depression and hypotension are dose-dependent; have resuscitation equipment ready. Avoid in patients with severe hepatic impairment. Coadministration with opioids or benzodiazepines potentiates sedation and respiratory depression.
This medication will cause you to lose consciousness quickly and is only given by a healthcare professional.,You will be closely monitored during and after administration.,You may experience drowsiness, dizziness, or confusion after waking up; do not drive or operate machinery for 24 hours.,Inform your doctor if you have any allergies, porphyria, or liver/kidney disease.,Avoid alcohol and other sedatives for at least 24 hours after receiving this medication.
BREVITAL SODIUM is a potent anesthetic that causes rapid loss of consciousness and should only be administered by trained medical professionals.,You may experience temporary pain or burning at the injection site; report any persistent pain or swelling to your healthcare provider.,Drowsiness, dizziness, and confusion may persist for several hours after the procedure; do not drive or operate machinery for at least 24 hours.,Avoid alcohol and other sedatives for 24 hours before and after the procedure as they may increase side effects.,Inform your doctor if you have a history of porphyria, liver disease, or drug allergies.,If you are pregnant or breastfeeding, discuss the risks and benefits with your healthcare provider.
"The combination of methohexital, a barbiturate anesthetic, and mesoridazine, a phenothiazine antipsychotic, can lead to additive central nervous system (CNS) depression and respiratory depression due to synergistic pharmacodynamic effects on GABAergic and dopaminergic pathways. This interaction may result in enhanced sedation, hypotension, and increased risk of respiratory arrest, particularly during induction or maintenance of anesthesia. Patients with underlying respiratory or cardiovascular compromise are at heightened risk for severe adverse outcomes."
"Methohexital, a barbiturate anesthetic, induces cytochrome P450 (CYP) 3A4 enzyme activity, accelerating the hepatic metabolism of azelnidipine, a dihydropyridine calcium channel blocker. This results in reduced plasma concentrations and diminished antihypertensive efficacy of azelnidipine, potentially leading to inadequate blood pressure control during concurrent use."
"Concomitant use of Methohexital, a barbiturate anesthetic with central nervous system (CNS) depressant effects, and Guanfacine, an alpha-2 adrenergic agonist with sedative properties, can lead to additive CNS depression. This may result in enhanced sedation, respiratory depression, hypotension, and bradycardia. Patients may experience excessive drowsiness, impaired cognitive and motor function, and increased risk of falls or respiratory compromise, particularly during anesthesia induction or recovery."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about METHOHEXITAL SODIUM vs BREVITAL SODIUM, answered by our medical review team.
METHOHEXITAL SODIUM is a Barbiturate Anesthetic that works by Methohexital sodium is a barbiturate that acts as a GABA-A receptor agonist, enhancing chloride conductance and causing neuronal hyperpolarization. It produces rapid sedation and anesthesia by depressing the central nervous system.. BREVITAL SODIUM is a Barbiturate Anesthetic that works by Brevital sodium (methohexital) is a barbiturate that acts as a GABA-A receptor agonist, enhancing chloride ion influx and hyperpolarizing neurons, leading to rapid sedation and anesthesia.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between METHOHEXITAL SODIUM and BREVITAL SODIUM depend on the specific clinical indication. These are both Barbiturate Anesthetic agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of METHOHEXITAL SODIUM is: Induction of anesthesia: 1-1.5 mg/kg IV bolus over 15-30 seconds. Maintenance: intermittent IV boluses of 20-40 mg every 4-7 minutes as needed.. The standard adult dose of BREVITAL SODIUM is: Induction of anesthesia: 1-1.5 mg/kg IV bolus over 15 seconds; maintenance: 0.5-1 mg/kg IV bolus as needed or 50-150 mcg/kg/min IV infusion.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between METHOHEXITAL SODIUM and BREVITAL SODIUM in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. METHOHEXITAL SODIUM is classified as Category C. Methohexital sodium is a barbiturate anesthetic. Use in the first trimester may be associated with a small increased risk of major malformations based on limited human data; animal. BREVITAL SODIUM is classified as Category C. Teratogenic potential not fully established in humans. In animal studies, methohexital caused fetal resorptions and malformations at maternally toxic doses. First trimester: Avoid . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.