Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
BUTABARBITAL vs SURITAL
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Butabarbital is a barbiturate that acts as a central nervous system depressant. It enhances the activity of GABA, an inhibitory neurotransmitter, by binding to the GABA-A receptor and prolonging the opening of chloride ion channels, leading to neuronal hyperpolarization and reduced excitability.
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.
Sedative,Hypnotic for short-term treatment of insomnia,Preoperative sedation
Induction of anesthesia,Maintenance of anesthesia as part of balanced anesthesia,Adjunct to regional anesthesia,Control of convulsive states (off-label)
50-100 mg orally or intramuscularly 3-4 times daily; maximum 400 mg/day.
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 30-50 hours in adults, which may be prolonged in elderly or patients with hepatic impairment, leading to accumulation with repeated dosing.
Terminal elimination half-life 2-8 hours (mean 4.5 h) in adults; prolonged in hepatic impairment.
Hepatic metabolism via cytochrome P450 enzymes (primarily CYP2C9 and CYP3A4); undergoes hydroxylation and glucuronidation; active metabolites include hydroxybutabarbital.
Primarily hepatic metabolism via microsomal enzyme oxidation (CYP2B6, CYP3A4) to inactive metabolites; minor renal excretion.
Primarily renal, with approximately 60-80% of the dose eliminated as metabolites (mostly hydroxylated and conjugated) and less than 5% as unchanged drug. Minor biliary/fecal excretion occurs (<10%).
Primarily renal excretion of metabolites; <1% unchanged. Minor biliary/fecal elimination.
Approximately 20-25% bound to plasma proteins, predominantly albumin.
~70% bound to albumin.
Approximately 1.0 L/kg, indicating distribution throughout total body water and extensive tissue binding.
1.5-2.5 L/kg; indicates extensive tissue distribution.
Oral bioavailability is nearly 100% (50-70% reported in some texts, but butabarbital is completely absorbed; first-pass metabolism is minimal).
IM: ~90%.
GFR 10-50 m L/min: reduce dose by 25%; GFR <10 m L/min: reduce dose by 50%.
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 50%; Child-Pugh class C: avoid use.
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).
Children 2-6 years: 25-50 mg orally 3-4 times daily; children 6-12 years: 50-100 mg orally 3-4 times daily; maximum 200 mg/day.
Induction: 3-6 mg/kg IV. Maintenance: 1-2 mg/kg IV as needed. Use with caution; not recommended for neonates.
Initiate at 25-50 mg orally 3 times daily; increase cautiously to avoid excessive sedation and falls, maximum 200 mg/day.
Reduce dose by 30-50% due to decreased clearance and increased sensitivity. Administer slowly and titrate to effect.
Butabarbital has no FDA boxed warning.
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.
Risk of dependence, tolerance, and withdrawal symptoms upon discontinuation; respiratory depression, especially with high doses or in patients with respiratory compromise; CNS depression may impair ability to drive or operate machinery; concomitant use with other CNS depressants (e.g., alcohol, opioids) increases risk of profound sedation and respiratory depression; geriatric patients may be more sensitive to effects; use with caution 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 barbiturates; porphyria (can exacerbate); severe respiratory insufficiency; history of addiction to sedative-hypnotics; acute or chronic pain (may cause paradoxical excitement); pregnancy (especially third trimester) and lactation.
Absolute: Known hypersensitivity to barbiturates, acute intermittent porphyria, severe respiratory insufficiency, status asthmaticus, and conditions where general anesthesia is contraindicated.
Grapefruit juice may decrease metabolism of butabarbital; avoid concurrent consumption. Alcohol increases CNS depression and should be avoided. No specific food restrictions otherwise.
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.
First trimester: Associated with increased risk of major congenital malformations, specifically oral clefts (relative risk ~2.0). Second/third trimester: Chronic use may lead to fetal dependence and withdrawal syndrome; neonatal respiratory depression if used near term; increased risk of neurobehavioral effects. Barbiturates cross the placenta rapidly.
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.
Butabarbital is excreted into breast milk in low concentrations. The milk-to-plasma ratio (M/P) is approximately 0.4–0.6. With therapeutic doses, infant serum levels are usually low; however, chronic high maternal doses may cause sedation or withdrawal in the nursing infant. Caution is recommended; alternate agents may be preferred if infant sedation occurs.
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 can alter butabarbital pharmacokinetics due to increased hepatic metabolism and volume of distribution. Serum concentrations may decrease; therapeutic drug monitoring is recommended if used chronically. Dose adjustments may be necessary to maintain efficacy, but due to risks, use is generally avoided. If used, start with lowest effective dose and monitor for clinical response and toxicity.
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.
Butabarbital is a short-acting barbiturate with rapid onset. It is primarily used for sedation and insomnia but has high abuse potential. Avoid use in patients with porphyria, severe hepatic impairment, or respiratory insufficiency. Abrupt discontinuation after prolonged use may precipitate withdrawal including seizures. Barbiturates induce CYP3A4 and other hepatic enzymes, reducing efficacy of oral contraceptives, warfarin, and corticosteroids. Use with caution in elderly due to increased risk of falls and cognitive impairment.
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.
Take exactly as prescribed; do not increase dose or frequency without consulting your doctor.,Do not stop taking suddenly as withdrawal reactions such as anxiety, tremors, or seizures can occur.,May cause drowsiness or dizziness; do not drive or operate machinery until you know how this medicine affects you.,Avoid alcohol and other central nervous system depressants (e.g., benzodiazepines, opioids) as they increase risk of severe sedation and respiratory depression.,Use effective contraception while taking this medication as it may reduce hormonal contraceptive effectiveness.,Store in a secure place away from children and others, as it can cause dependence and is habit-forming.
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.
"Butabarbital, a barbiturate, induces cytochrome P450 (CYP) enzymes, enhancing the hepatic metabolism of ketamine, a dissociative anesthetic primarily metabolized by CYP3A4 and CYP2B6. This interaction reduces ketamine's systemic exposure and anesthetic efficacy, potentially leading to suboptimal sedation or anesthesia. Additionally, concurrent use may increase the risk of respiratory depression and hypotension due to additive central nervous system (CNS) depressant effects."
"Butabarbital, a barbiturate, is a potent CNS depressant that acts primarily by potentiating GABA-A receptor activity. Metaxalone is a centrally acting muscle relaxant with sedative properties. Coadministration results in additive or synergistic CNS depression, leading to increased risk of excessive sedation, respiratory depression, impaired psychomotor function, and potential coma or death, especially at higher doses or in vulnerable patients."
"Butabarbital, a barbiturate sedative-hypnotic, induces hepatic cytochrome P450 enzymes, particularly CYP3A4, which are responsible for metabolizing the atypical antipsychotic paliperidone. This induction decreases plasma concentrations of paliperidone, potentially reducing its therapeutic efficacy in treating schizophrenia or bipolar disorder. Concomitant use may lead to relapse of psychiatric symptoms or necessitate dose adjustments."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about BUTABARBITAL vs SURITAL, answered by our medical review team.
BUTABARBITAL is a Barbiturate that works by Butabarbital is a barbiturate that acts as a central nervous system depressant. It enhances the activity of GABA, an inhibitory neurotransmitter, by binding to the GABA-A receptor and prolonging the opening of chloride ion channels, leading to neuronal hyperpolarization and reduced excitability.. 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 BUTABARBITAL and SURITAL depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of BUTABARBITAL is: 50-100 mg orally or intramuscularly 3-4 times daily; maximum 400 mg/day.. 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 BUTABARBITAL 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. BUTABARBITAL is classified as Category C. First trimester: Associated with increased risk of major congenital malformations, specifically oral clefts (relative risk ~2.0). Second/third trimester: Chronic use may lead to fe. 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.