Methohexital (Brevital)

Electroconvulsive Therapy (ECT) agent of choice - Rapid recovery and less anticonvulsant effect than thiopental preserve seizure duration; 0.5-1 mg/kg.

Rapid induction - Onset about 30 s with brief duration and smooth quick emergence.

Pain on injection - Common; precede with lidocaine or use a larger vein.

Myoclonus and hiccups - More frequent than with thiopental and not epileptiform.

Porphyria - Contraindicated in acute intermittent porphyria; induces ALA synthase.

Respiratory depression - Dose-dependent apnea; have airway equipment ready.

Excessive effect - Supportive care only: airway, ventilation, fluids/pressors for hypotension; no reversal agent.

Drug Interactions - Additive CNS and respiratory depression with opioids and benzodiazepines; precipitates with acidic drugs such as succinylcholine.

Pediatric Implications - Rectal 25 mg/kg or IM 6.6-10 mg/kg for pediatric induction/sedation.

Obstetric Implications - Crosses the placenta and can cause neonatal depression; not commonly used for obstetric anesthesia.

Absolute:

Acute intermittent or variegate porphyria

Relative:

Severe hypovolemia or shock

Status asthmaticus

Caution:

Cardiac disease

Hepatic impairment

Seizure disorder

Induction: 1-1.5 mg/kg IV.

Electroconvulsive therapy: 0.5-1 mg/kg IV.

6.6-10 mg/kg (pediatric)

Enhances GABA-A receptor chloride conductance and depresses the reticular activating system.

Hepatic

Renal

DEA Schedule IV.

Reconstitute to 1% (10 mg/mL).

Incompatible with acidic solutions (atropine, succinylcholine) - precipitates.

Rectal induction dose 25 mg/kg in children.