Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
METHOHEXITAL SODIUM vs SURITAL
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.
SURITAL (thiamylal) is an ultra-short-acting barbiturate that enhances GABA-A receptor activity, increasing chloride ion conductance and neuronal hyperpolarization, resulting in rapid induction of 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 of anesthesia,Maintenance of anesthesia as part of balanced anesthesia,Adjunct to regional anesthesia,Control of convulsive states (off-label)
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: 3-5 mg/kg IV bolus over 10-15 seconds. Maintenance: 0.5-1.5 mg/kg IV as needed for anesthesia. Also used as 0.2-0.4% solution for IV infusion at 0.5-2 mg/min.
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 2-8 hours (mean 4.5 h) in adults; prolonged in hepatic impairment.
Primarily hepatic metabolism via CYP2B6 and other microsomal enzymes; undergoes oxidation and glucuronidation. Active metabolites are minimally important.
Primarily hepatic metabolism via microsomal enzyme oxidation (CYP2B6, CYP3A4) to inactive metabolites; minor renal excretion.
Renal: <1% unchanged; hepatic metabolism followed by renal excretion of metabolites accounts for >95% of elimination. Fecal: negligible (<1%).
Primarily renal excretion of metabolites; <1% unchanged. Minor biliary/fecal elimination.
85–90% bound to albumin.
~70% bound to albumin.
2.0–3.0 L/kg; context: High Vd due to extensive tissue distribution, especially to adipose tissue.
1.5-2.5 L/kg; indicates extensive tissue distribution.
Intramuscular: ~90–100%; Rectal: ~70–80%; Oral: not available (inactive due to first-pass metabolism).
IM: ~90%.
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 specific GFR-based adjustments; metabolized primarily in liver. Caution in severe renal impairment due to potential accumulation of inactive metabolites.
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% and titrate to effect. Child-Pugh C: Contraindicated or use with extreme caution with reduced doses (e.g., 25-50% of normal).
Induction: 1-2 mg/kg IV bolus. Maintenance: 0.5-1 mg/kg IV bolus as needed. Maximum single dose: 100 mg.
Induction: 3-6 mg/kg IV. Maintenance: 1-2 mg/kg IV as needed. Use with caution; not recommended for neonates.
Reduce initial dose by 25-50% (0.5-1 mg/kg IV) and titrate slowly due to increased sensitivity and prolonged recovery.
Reduce dose by 30-50% due to decreased clearance and increased sensitivity. Administer slowly and titrate to effect.
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.
WARNING: RESPIRATORY DEPRESSION AND CARDIAC ARREST. SURITAL may cause severe respiratory depression or apnea, especially with rapid administration. Resuscitative equipment and personnel trained in airway management must be immediately available. Avoid intra-arterial injection due to risk of arteriospasm, thrombosis, and gangrene.
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
Monitor respiratory and cardiac function continuously; use with caution in patients with respiratory compromise, hypotension, shock, or hepatic/renal impairment; may cause laryngospasm, bronchospasm, or hypotension; avoid extravasation; use with caution in porphyria.
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
Absolute: Known hypersensitivity to barbiturates, acute intermittent porphyria, severe respiratory insufficiency, status asthmaticus, and conditions where general anesthesia is contraindicated.
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 reported for Surital (thiamylal). However, patients should avoid consuming grapefruit or grapefruit juice for 24 hours before and after administration, as it may theoretically inhibit cytochrome P450 metabolism, although significant interactions are not well-documented.
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.
Pregnancy Category D (positive evidence of human fetal risk). First trimester: Risk of congenital anomalies (limb defects, CNS malformations) based on animal studies and limited human data. Second/third trimester: Increased risk of preterm labor, fetal bradycardia, neonatal respiratory depression, and withdrawal syndrome. Avoid use during pregnancy unless clearly needed.
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 breast milk is unknown; M/P ratio not established. Due to high lipid solubility, potential for significant transfer. Consider risks of neonatal CNS depression. Use with caution; monitor infant for sedation, poor feeding, and respiratory depression. Alternative agents preferred.
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.
Increased volume of distribution and hepatic metabolism in pregnancy may require higher induction doses and more frequent maintenance doses. However, due to fetal risks, avoid use in pregnancy unless absolutely necessary. If used, start at lower range (e.g., 3-4 mg/kg IV induction) and titrate to effect. No established dose adjustment guidelines; individualize based on clinical response and close 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.
Surital (thiamylal) is an ultra-short-acting barbiturate used for induction of anesthesia. Due to its high lipid solubility, onset of action is rapid (<30 seconds). It is contraindicated in porphyria and should be used with caution in patients with hepatic impairment, as it is metabolized in the liver. Extravasation causes tissue necrosis; use a large vein for IV administration. Respiratory depression and laryngospasm are common during induction. Surital has no analgesic properties and may cause myocardial depression at high doses. For short procedures, it provides rapid awakening but with potential residual sedation.
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.
This medication is used to put you to sleep before surgery or certain procedures.,You may feel dizzy or drowsy for several hours after receiving this drug; do not drive or operate machinery for at least 24 hours.,Avoid alcohol for at least 24 hours after receiving this medication as it can increase side effects.,Inform your healthcare provider if you have a history of porphyria, liver disease, or respiratory problems.,Do not breastfeed for at least 24 hours after administration without consulting your doctor.,Notify your doctor immediately if you experience severe pain, redness, or swelling at the injection site.,You may experience temporary confusion or memory loss after waking up; this is normal and should resolve.
"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 SURITAL, 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.. SURITAL is a Barbiturate Anesthetic that works by SURITAL (thiamylal) is an ultra-short-acting barbiturate that enhances GABA-A receptor activity, increasing chloride ion conductance and neuronal hyperpolarization, resulting in rapid induction of anesthesia.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between METHOHEXITAL SODIUM and SURITAL 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 SURITAL is: Induction: 3-5 mg/kg IV bolus over 10-15 seconds. Maintenance: 0.5-1.5 mg/kg IV as needed for anesthesia. Also used as 0.2-0.4% solution for IV infusion at 0.5-2 mg/min.. 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 SURITAL 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. SURITAL is classified as Category C. Pregnancy Category D (positive evidence of human fetal risk). First trimester: Risk of congenital anomalies (limb defects, CNS malformations) based on animal studies and limited hu. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.