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Methohexital Dosage

Applies to the following strengths: 5 g; 500 mg; 2.5 g; 100 mg/10 mL; 200 mg

The information at is not a substitute for medical advice. Always consult your doctor or pharmacist.

Usual Adult Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for Anesthesia

Induction of anesthesia:
A 1% solution is administered intravenously at a rate of about 1 mL/5 seconds. Gaseous anesthetics and/or skeletal muscle relaxants may be administered concomitantly. The dose required for induction may range from 50 to 120 mg or more but averages about 70 mg. The usual dosage in adults ranges from 1 to 1.5 mg/kg. The induction dose usually provides anesthesia for 5 to 7 minutes.
Maintenance of anesthesia:
Maintenance of anesthesia may be accomplished by intermittent injections of the 1% solution or by continuous intravenous infusion of a 0.2% solution. Intermittent injections of about 20 to 40 mg may be given as required, usually every 4 to 7 minutes. For continuous infusion, the average rate of administration is about 3 mL of a 0.2% solution/minute. The rate of flow must be individualized for each patient. For longer surgical procedures, gradual reduction in the rate of administration is recommended. Other parenteral agents, usually narcotic analgesics, are ordinarily employed along with methohexital during longer procedures.

Usual Pediatric Dose for Anesthesia

For induction of anesthesia:
1 month or older:

Intramuscular: 6.6 to 10 mg/kg using a 5% solution.
Rectal: 25 mg/kg using a 1% solution.

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available


Methohexital should be administered intravenously in a concentration of no higher than 1%. Higher concentrations markedly increase the incidence of muscular movements and irregularities in respiration and blood pressure.


Data not available