Methohexital

Mechanism :

Methohexital is an ultra-short-acting IV barbiturate anaesthetic.

Indication :

Induction of anaesthesia
Procedural sedation
Off-Label: Wada test

Contraindications :

Hypersensitivity to methohexital or any component of the formulation; patients in whom general anaesthesia is contraindicated.

Dosing :

Induction of anaesthesia:

≥1 month:

IM: 6.6 to 10 mg/kg of 5% solution

Rectal: 25 mg/kg of a 1% solution

Procedural sedation: IV:

Initial: 0.5 mg/kg of a 1% solution given immediately prior to procedure.

Adverse Effect :

Circulatory depression, circulatory shock, hypotension, Anxiety, delirium (emergence), headache, involuntary muscle movements, erythema, pruritus, Abdominal pain, hiccups, nausea, Increased serum transaminases, Apnea, bronchospasm, cough, dyspnea.

Interaction :

Calcium Channel Blockers: Barbiturates may increase the metabolism of Calcium Channel Blockers.
CNS Depressants: May enhance the adverse/toxic effect of other CNS Depressants.
Estrogen Derivatives & progestins: Barbiturates may diminish the therapeutic effect of Estrogen Derivatives and progestins.
Opioid Analgesics: CNS Depressants may enhance the CNS depressant effect of Opioid Analgesics.
Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors.
Tricyclic Antidepressants: Barbiturates may increase the metabolism of Tricyclic Antidepressants.

Hepatic Dose :

Use with caution and reduce dose.