Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
PROPOFOL vs ETHRANE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Propofol enhances the activity of gamma-aminobutyric acid (GABA) at GABA-A receptors, leading to increased chloride conductance, neuronal hyperpolarization, and anesthetic effects. It also inhibits N-methyl-D-aspartate (NMDA) receptors and modulates calcium influx via L-type calcium channels.
Enflurane is a volatile inhalational anesthetic that potentiates GABA-A receptor activity and inhibits excitatory neurotransmission, resulting in general anesthesia.
Induction and maintenance of general anesthesia,Sedation for intubated, mechanically ventilated patients in the ICU,Procedural sedation (e.g., during diagnostic or therapeutic procedures),Treatment of refractory status epilepticus (off-label),Management of severe agitation or delirium (off-label)
Induction and maintenance of general anesthesia
Induction: 2-2.5 mg/kg IV bolus. Maintenance: 25-75 mcg/kg/min IV infusion. For sedation: 25-100 mcg/kg/min IV.
1-5% inspired concentration via inhalation, titrated to effect for maintenance of general anesthesia.
Terminal elimination half-life: 4-7 hours (after prolonged infusion, context-sensitive half-life increases up to 60 minutes after 8-hour infusion).
Context-sensitive half-life: approximately 2-5 minutes after short procedures; prolonged after prolonged administration due to slow washout from fat stores.
Primarily hepatic via conjugation to glucuronide and sulfate; also metabolized by CYP2B6 and CYP2C9. Metabolites are renally excreted.
Primarily hepatic via cytochrome P450 (CYP2E1); minor metabolism to fluoride ions.
Renal: <1% unchanged; hepatic metabolism to inactive glucuronide and sulfate conjugates, excreted renally (≈88%) and fecally (≈1-2%).
Primarily exhaled unchanged via lungs (>95%); less than 5% metabolized in liver to fluoride ion and other metabolites, with renal excretion of metabolites.
95-99% bound primarily to albumin (≈48%) and alpha-1-acid glycoprotein (≈50%), with minor binding to lipoproteins.
Approximately 30-40%, primarily to albumin.
Initial Vd: 0.2-0.4 L/kg (central compartment); steady-state Vd: 2-10 L/kg (extensive tissue distribution).
Vd: 1.2-2.0 L/kg, indicating extensive distribution into tissues, especially fat.
IV: 100%; enteral: negligible due to first-pass metabolism; oral bioavailability <1%.
By inhalation: 100% as delivered; not administered orally.
No dose adjustment required for GFR >10 m L/min. For GFR <10 m L/min, use with caution due to propylene glycol accumulation, monitor for metabolic acidosis.
No dose adjustment required for GFR >10 m L/min; use with caution in severe renal impairment (GFR <10 m L/min) due to potential accumulation of inorganic fluoride metabolites.
Child-Pugh A: No adjustment. Child-Pugh B: Reduce dose by 50%. Child-Pugh C: Avoid use or reduce by 75% due to prolonged clearance and risk of hypotension.
No specific Child-Pugh based adjustment; use with caution in severe hepatic impairment as metabolism may be decreased.
Induction: 2.5-3.5 mg/kg IV over 30 sec. Maintenance: 125-300 mcg/kg/min for age <3 years; 100-200 mcg/kg/min for age 3-12 years. For sedation: 25-100 mcg/kg/min.
Induction: 2-5% inspired concentration; Maintenance: 1-3% inspired concentration, adjusted to age and response.
Reduce induction dose to 1-1.5 mg/kg IV; decrease infusion rate by 20-50% due to reduced clearance and increased sensitivity.
Lower inspired concentrations (0.5-2%) recommended due to increased sensitivity and reduced clearance; titrate to effect.
No FDA black box warnings.
None
Hypotension and bradycardia: may require fluid resuscitation or vasopressors,Respiratory depression and apnea: must have airway management equipment available,Propofol infusion syndrome (PRIS): rare but fatal with high doses >4 mg/kg/hr for >48 hours; characterized by metabolic acidosis, rhabdomyolysis, hyperkalemia, and cardiac failure,Risk of pancreatitis: monitor lipase if symptoms develop,Abrupt discontinuation may cause withdrawal symptoms after prolonged use,Not recommended for use in patients with propofol allergy or egg/soybean oil hypersensitivity (formulation contains egg lecithin and soybean oil)
May cause dose-dependent cardiovascular depression,Risk of malignant hyperthermia,Potential for nephrotoxicity due to fluoride release,Hepatotoxicity risk, especially with repeated use,Neurologic effects including seizure activity at high doses
Hypersensitivity to propofol or any component of the formulation (including egg lecithin, soybean oil, or disodium edetate),Patients with severe lipid metabolism disorders (e.g., pancreatitis with hypertriglyceridemia),Not for use in general anesthesia in obstetrics (crosses placenta; may cause neonatal depression),Relative: hypovolemia, hemodynamic instability, increased intracranial pressure (use with caution)
Known hypersensitivity to enflurane or other halogenated anesthetics,Known or suspected susceptibility to malignant hyperthermia,Severe hepatic impairment,Uncontrolled epilepsy
No specific food restrictions. However, propofol is formulated in a lipid emulsion containing soybean oil and egg lecithin, which may interact with high-fat meals theoretically but not clinically significant. Avoid alcohol for 24 hours post-procedure due to additive sedative effects.
No specific food interactions. Patient must follow preoperative fasting guidelines (nil per os, NPO) as directed by anesthesiologist to reduce risk of aspiration.
First trimester: Propofol is not associated with major congenital malformations based on limited human data, but animal studies show developmental toxicity at high doses. Second trimester: No clear evidence of fetal harm. Third trimester: Use may cause neonatal respiratory depression, hypotonia, and neurobehavioral effects; risk of fetal bradycardia and hypoxia. Propofol crosses the placenta rapidly.
FDA Category B. No evidence of teratogenicity in animal studies; human data limited. Use only if clearly needed during pregnancy, especially first trimester due to potential fetal hypoxia from maternal hypotension.
Propofol is excreted into breast milk in very low concentrations, with an estimated M/P ratio of 1.2-1.5. The relative infant dose is <0.1% of weight-adjusted maternal dose. Consider discarding milk for 24 hours after administration due to potential sedative effects on the infant.
Excreted in breast milk in low amounts; M/P ratio not established. Consider benefits of breastfeeding vs. risk of infant exposure. Minimal systemic absorption in infant expected.
Pregnancy increases volume of distribution and clearance of propofol by 20-50%, primarily due to increased cardiac output and hepatic blood flow. Induction doses may need to be increased by 15-30% to achieve desired effect. Maintenance infusion rates may also require upward titration.
No specific dose adjustments required for pregnancy; however, MAC decreases by approximately 30% during pregnancy due to hormonal changes and increased progesterone. Monitor depth of anesthesia closely.
Propofol causes dose-dependent respiratory depression and apnea; always have airway equipment ready. It reduces cerebral metabolic rate and intracranial pressure, making it useful for neuroanesthesia. Pain on injection is common, particularly in small veins; consider lidocaine pretreatment. Propofol infusion syndrome (PRIS) is a rare but fatal complication with prolonged high-dose infusions (>48h, >4 mg/kg/h), characterized by lactic acidosis, rhabdomyolysis, and cardiac failure. Avoid in patients with egg or soy allergy due to lipid emulsion. Use the lower dose for elderly or hemodynamically unstable patients. Monitor triglyceride levels with prolonged use.
ETHRANE (enflurane) is a potent inhalation anesthetic. Its use is limited due to risk of seizures at high doses and potential for nephrotoxicity from fluoride ion release. Avoid in patients with history of seizures or renal impairment. Rapid induction and recovery; use with caution in hypotensive patients due to myocardial depression. Malignant hyperthermia trigger.
This medication will cause you to feel very sleepy and lose consciousness quickly.,You may experience a burning or stinging sensation at the injection site; this is common.,Do not drive, operate machinery, or make important decisions for at least 24 hours after receiving this medication.,You might feel groggy, dizzy, or have a headache after waking up.,Inform your doctor if you have any allergies, especially to eggs, soy, or peanuts.,If you will be receiving this medication for a prolonged period, your doctor will monitor your heart, kidneys, and blood tests.
You will receive this anesthesia medication only in a hospital setting under expert supervision.,Possible side effects include nausea, vomiting, shivering, and confusion after waking up.,Tell your doctor if you have a history of seizures, kidney problems, or muscle disorders.,Avoid driving or operating machinery for at least 24 hours after anesthesia.,Do not eat or drink for the time specified by your healthcare team before surgery.
"Propofol, a general anesthetic, may inhibit CYP2C8, the primary enzyme responsible for rosiglitazone metabolism, leading to decreased clearance and elevated plasma concentrations of rosiglitazone. This interaction can potentiate the hypoglycemic effects of rosiglitazone, increasing the risk of hypoglycemia. Clinical vigilance is warranted when these agents are coadministered, especially in patients with diabetes."
"The combination of propofol and methyldopa can lead to an increased risk of severe hypotension and bradycardia due to additive cardiovascular depressant effects. Propofol causes peripheral vasodilation and direct myocardial depression, while methyldopa reduces sympathetic outflow and depletes catecholamines, enhancing propofol's hemodynamic effects. This interaction may result in profound hypotension, reduced cardiac output, and risk of organ hypoperfusion during anesthesia induction and maintenance."
"Propofol, a GABA-A receptor agonist and general anesthetic, depresses myocardial contractility and reduces systemic vascular resistance, leading to hypotension and bradycardia. Pindolol, a non-selective beta-blocker with intrinsic sympathomimetic activity, can blunt the compensatory tachycardia in response to propofol-induced vasodilation and myocardial depression. Concurrent use may result in additive negative chronotropic and inotropic effects, potentially causing severe bradycardia, hypotension, or reduced cardiac output, especially in patients with compromised cardiac function or hypovolemia."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about PROPOFOL vs ETHRANE, answered by our medical review team.
PROPOFOL is a General Anesthetic that works by Propofol enhances the activity of gamma-aminobutyric acid (GABA) at GABA-A receptors, leading to increased chloride conductance, neuronal hyperpolarization, and anesthetic effects. It also inhibits N-methyl-D-aspartate (NMDA) receptors and modulates calcium influx via L-type calcium channels.. ETHRANE is a General Anesthetic that works by Enflurane is a volatile inhalational anesthetic that potentiates GABA-A receptor activity and inhibits excitatory neurotransmission, resulting in general anesthesia.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between PROPOFOL and ETHRANE 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 PROPOFOL is: Induction: 2-2.5 mg/kg IV bolus. Maintenance: 25-75 mcg/kg/min IV infusion. For sedation: 25-100 mcg/kg/min IV.. The standard adult dose of ETHRANE is: 1-5% inspired concentration via inhalation, titrated to effect for maintenance of general anesthesia.. 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 PROPOFOL and ETHRANE 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. PROPOFOL is classified as Category A/B. First trimester: Propofol is not associated with major congenital malformations based on limited human data, but animal studies show developmental toxicity at high doses. Second tr. ETHRANE is classified as Category C. FDA Category B. No evidence of teratogenicity in animal studies; human data limited. Use only if clearly needed during pregnancy, especially first trimester due to potential fetal . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.