Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ETOMIDATE vs DIPRIVAN
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Etomidate is a nonbarbiturate hypnotic agent that acts as a positive allosteric modulator of the gamma-aminobutyric acid (GABA) type A receptor, enhancing GABA-mediated inhibition in the central nervous system. It produces rapid anesthesia with minimal cardiovascular and respiratory depression.
Propofol potentiates GABA-A receptor activity, leading to rapid sedation and hypnosis by enhancing chloride conductance and neuronal hyperpolarization.
Induction of general anesthesia,Procedural sedation (off-label),Rapid sequence intubation (off-label)
Induction and maintenance of general anesthesia,Sedation for intubated, mechanically ventilated patients in intensive care units,Monitored anesthesia care (MAC) sedation,Treatment of refractory status epilepticus (off-label),Procedural sedation (off-label)
Induction: 0.2–0.6 mg/kg IV over 30–60 seconds. Maintenance: 10–20 mcg/kg/min IV continuous infusion.
Induction: 2-2.5 mg/kg IV bolus; maintenance: 25-75 mcg/kg/min IV infusion.
Terminal elimination half-life: 2.9–5.3 hours (context: redistribution shortens clinical effect; hepatic impairment prolongs).
Terminal elimination half-life: 4-7 hours (with context of context-sensitive half-life increasing after prolonged infusion).
Etomidate is extensively metabolized in the liver via hydrolysis of the ester side chain by hepatic esterases to its principal metabolite, etomidate carboxylic acid. A minor metabolite is formed via N-demethylation. Metabolites are inactive.
Primarily hepatic conjugation to inactive metabolites (propofol glucuronide), with minor metabolism via CYP2B6 and CYP2C9 to 4-hydroxypropofol.
Renal: 75% as metabolite (carboxylic acid), 2% unchanged; fecal/biliary: minimal.
Renal (approximately 88% as metabolites, <1% unchanged); fecal (approximately 2%); other (10% as metabolites via other routes).
76% bound to albumin.
95-99% bound, primarily to albumin.
Vd: 2.5–4.5 L/kg (large, indicating extensive tissue uptake).
2-10 L/kg (large Vd indicating extensive tissue distribution).
IV: 100% (only route used clinically).
Intravenous: 100%; not available orally due to extensive first-pass metabolism.
No dose adjustment required for renal impairment. Hemodialysis does not alter dosing. Use caution in severe renal failure due to propylene glycol vehicle if prolonged infusion.
No adjustment required; propofol is not significantly renally eliminated.
No specific adjustment for Child-Pugh class. However, prolonged effect may occur in severe hepatic impairment; reduce induction dose by 50% and titrate to effect.
No specific Child-Pugh based guidelines; use lower doses due to impaired clearance, especially in cirrhosis.
Induction: 0.2–0.6 mg/kg IV (max 40 mg). Age >10 years: use adult dosing. Neonates and infants: reduce dose to 0.3 mg/kg due to higher volume of distribution.
Induction: 2.5-3.5 mg/kg IV bolus; maintenance: 125-300 mcg/kg/min IV infusion. Not approved for ICU sedation in <16 years.
Induction: 0.15–0.3 mg/kg IV (50% reduction of adult dose) due to decreased clearance and increased sensitivity. Use lower end of dosing range.
Reduce induction dose to 1-1.5 mg/kg IV bolus and maintenance infusion to 20-50 mcg/kg/min IV due to increased sensitivity and decreased clearance.
Etomidate has been associated with mortality in children. It should not be used in children younger than 6 months of age. (This warning is included in the prescribing information based on FDA labeling; specific text may vary.)
Propofol should be administered only by persons trained in the administration of general anesthesia and not involved in the conduct of the surgical/diagnostic procedure. Patients should be continuously monitored for early signs of hypotension, bradycardia, apnea, airway obstruction, and oxygen desaturation. For sedation of intubated, mechanically ventilated patients in the ICU, propofol should be used with caution in patients with increased intracranial pressure or impaired cerebral circulation.
Inhibition of adrenal steroidogenesis (adrenal suppression) due to blockade of 11-beta-hydroxylase, leading to decreased cortisol and aldosterone production; may persist for 12-24 hours after single dose,Myoclonic movements during induction (involuntary muscle contractions),Hypotension and bradycardia (less common than with other induction agents),Venous irritation and pain on injection (may be reduced by using larger veins)
Risk of hypotension and bradycardia, especially in elderly or hypovolemic patients,Respiratory depression and apnea requiring airway management,Propofol infusion syndrome (PRIS): metabolic acidosis, rhabdomyolysis, renal failure, cardiac failure, especially with prolonged high-dose infusions,Hypertriglyceridemia; monitor lipids with prolonged use,Risk of pancreatitis,Use with caution in patients with epilepsy; may increase seizure risk during withdrawal,May cause green discoloration of urine, hair, or nails
Hypersensitivity to etomidate,Patients with acute porphyria (may be porphyrinogenic)
Hypersensitivity to propofol or any component of the formulation,Hypersensitivity to eggs, egg products, soybeans, or soy products (due to lipid vehicle),Patients with severe lipid metabolism disorders (e.g., hyperlipidemia),Not recommended for general anesthesia in patients with increased intracranial pressure or impaired cerebral circulation unless benefits outweigh risks
No specific food interactions are known. Etomidate is administered intravenously and does not have oral bioavailability. However, concurrent use of drugs that affect CYP3A4 (e.g., grapefruit juice) is not clinically significant due to IV route.
No specific food interactions; however, propofol emulsion contains soybean oil and egg lecithin, so avoid in patients with egg or soy allergies. The emulsion can be contaminated if bottle is reused; discard after single use. No dietary restrictions required for administration.
Etomidate is classified as FDA Pregnancy Category C. Animal studies have shown embryotoxicity and teratogenicity at doses higher than human doses. There are no adequate and well-controlled studies in pregnant women. First trimester exposure may be associated with a slightly increased risk of congenital malformations, but data are limited. Risks to the fetus should be weighed against the benefits of maternal anesthesia. The drug is not recommended during pregnancy unless clearly needed, especially during organogenesis. In the second and third trimesters, etomidate may cause fetal central nervous system depression and respiratory depression if used near term.
Propofol (DIPRIVAN) is Pregnancy Category B. Animal studies at clinical doses did not show teratogenicity. Use in first trimester only if clearly needed. During second and third trimesters, propofol crosses the placenta and may cause neonatal respiratory depression and neurobehavioral depression. Risk of fetal acidosis and bradycardia. No major teratogenic effects reported in human studies, but limited data.
It is unknown whether etomidate is excreted in human breast milk. The molecular weight (244.3) suggests potential excretion into milk. The milk-to-plasma ratio (M/P) has not been determined. Due to the short half-life (2–5 hours) and use as a single induction dose, transfer to the infant is likely minimal. However, caution is advised. The American Academy of Pediatrics classifies etomidate as 'compatible' with breastfeeding after a single dose, but data are insufficient for repeated or prolonged use. Infants should be monitored for sedation and respiratory depression.
Propofol is excreted into breast milk in low concentrations. M/P ratio not established. Due to low oral bioavailability, risk to infant is minimal. However, caution is advised due to potential CNS depression in neonates. The manufacturer recommends discontinuing breastfeeding for 24 hours after administration.
No specific dose adjustments are recommended for etomidate during pregnancy, but the dose should be individualized to achieve the desired level of anesthesia with the lowest effective dose. Physiologic changes in pregnancy (e.g., increased plasma volume, altered protein binding) may affect pharmacokinetics, but etomidate is rapidly redistributed and has a short duration of action. The standard induction dose of 0.2–0.6 mg/kg IV is used. Close monitoring of maternal and fetal status is advised. In cesarean section, lower doses may be considered to reduce fetal depression.
Pharmacokinetic changes in pregnancy include increased volume of distribution and clearance, particularly in the third trimester. No specific dose adjustment guidelines; clinical response and patient condition determine dosing. Reduced doses may be required due to increased sensitivity to propofol in pregnancy.
Etomidate is an induction agent of choice in hemodynamically unstable patients due to minimal cardiovascular depression. Adrenal suppression occurs even after a single dose, manifesting as decreased cortisol and aldosterone synthesis via 11β-hydroxylase inhibition. Administer slowly over 30-60 seconds to reduce myoclonus and pain on injection. Use a lower dose (0.2-0.3 mg/kg IV) in elderly or debilitated patients. Etomidate is not recommended for rapid sequence intubation in septic shock due to risk of adrenal insufficiency; consider ketamine as alternative. Prolonged infusion is not advised due to propylene glycol vehicle and adrenal suppression.
DIPRIVAN (propofol) causes pain on injection, especially in small veins; pretreatment with lidocaine or use of a larger vein can mitigate. It is formulated as a lipid emulsion containing soybean oil and egg lecithin, thus contraindicated in patients with egg or soybean allergies. Propofol can cause profound hypotension and respiratory depression; ensure airway equipment and vasopressors are immediately available. The infusion syndrome (PRIS) is rare but lethal, characterized by metabolic acidosis, rhabdomyolysis, and cardiac failure; avoid prolonged high-dose infusions (>5 mg/kg/hr for >48 hours).
You may experience brief involuntary muscle movements during injection, which are usually harmless.,Tell your doctor if you have adrenal gland problems or are taking corticosteroids.,This drug may cause a temporary decrease in your body's ability to produce stress hormones.,Avoid driving or operating machinery until the effects of the medication have completely worn off.,Report any severe pain at the injection site or unusual weakness after the procedure.
You will be monitored continuously during and after administration due to risk of low blood pressure and slowed breathing.,You may feel a burning or stinging sensation at the injection site; inform your healthcare provider if it persists.,Do not drive or operate machinery for at least 24 hours after receiving propofol due to residual sedation.,Inform your medical team if you have allergies to eggs, soy, or sesame seeds.,Propofol is not intended for home use; it is only administered in a supervised medical setting.
"Concurrent administration of etomidate and fluoxetine may potentiate the anesthetic and sedative effects, as fluoxetine inhibits CYP3A4 which is involved in the metabolism of etomidate, leading to increased etomidate plasma concentrations and prolonged recovery time. Additionally, both drugs can cause QTc interval prolongation, increasing the risk of torsades de pointes and other ventricular arrhythmias. Patients may experience enhanced central nervous system depression, respiratory depression, and hypotension."
"The combination of Promazine, a phenothiazine antipsychotic with strong alpha-adrenergic blocking activity, and Etomidate, a non-barbiturate hypnotic used for induction of anesthesia, can lead to an increased risk of hypotension due to additive vasodilatory effects. Promazine's alpha-1 receptor antagonism impairs compensatory vasoconstriction, while Etomidate suppresses adrenal cortisol synthesis, potentially blunting the stress response and further reducing hemodynamic stability. Clinically, this interaction may result in profound hypotension, especially in hypovolemic or elderly patients, requiring careful dose titration and monitoring."
"The coadministration of oxazepam, a benzodiazepine that enhances GABA-A receptor activity, with etomidate, a non-barbiturate anesthetic that also potentiates GABA-A receptor function, results in additive central nervous system (CNS) depression. This synergistic interaction can lead to excessive sedation, respiratory depression, hypotension, and prolonged recovery from anesthesia. Patients are at increased risk of apnea, hypoxia, and hemodynamic instability, particularly during induction and maintenance of anesthesia."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ETOMIDATE vs DIPRIVAN, answered by our medical review team.
ETOMIDATE is a General Anesthetic that works by Etomidate is a nonbarbiturate hypnotic agent that acts as a positive allosteric modulator of the gamma-aminobutyric acid (GABA) type A receptor, enhancing GABA-mediated inhibition in the central nervous system. It produces rapid anesthesia with minimal cardiovascular and respiratory depression.. DIPRIVAN is a General Anesthetic that works by Propofol potentiates GABA-A receptor activity, leading to rapid sedation and hypnosis by enhancing chloride conductance and neuronal hyperpolarization.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ETOMIDATE and DIPRIVAN depend on the specific clinical indication. These are both General 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 ETOMIDATE is: Induction: 0.2–0.6 mg/kg IV over 30–60 seconds. Maintenance: 10–20 mcg/kg/min IV continuous infusion.. The standard adult dose of DIPRIVAN is: Induction: 2-2.5 mg/kg IV bolus; maintenance: 25-75 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 ETOMIDATE and DIPRIVAN 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. ETOMIDATE is classified as Category C. Etomidate is classified as FDA Pregnancy Category C. Animal studies have shown embryotoxicity and teratogenicity at doses higher than human doses. There are no adequate and well-co. DIPRIVAN is classified as Category C. Propofol (DIPRIVAN) is Pregnancy Category B. Animal studies at clinical doses did not show teratogenicity. Use in first trimester only if clearly needed. During second and third tr. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.