indication

Used for the production of complete anaesthesia of short duration, for the induction of general anaesthesia, and for inducing a hypnotic state.

pharmacology

Thiamylal, a barbiturate, is used in combination with acetaminophen or aspirin and caffeine for its sedative and relaxant effects in the treatment of tension headaches, migraines, and pain. Barbiturates act as nonselective depressants of the central nervous system (CNS), capable of producing all levels of CNS mood alteration from excitation to mild sedation, hypnosis, and deep coma. In sufficiently high therapeutic doses, barbiturates induce anesthesia.

mechanism of action

Thiamylal binds at a distinct binding site associated with a Cl^- ionopore at the GABA_A receptor, increasing the duration of time for which the Cl^- ionopore is open. The post-synaptic inhibitory effect of GABA in the thalamus is, therefore, prolonged.

toxicity

Intravenous LD50 in rat is 51 mg/kg.

biotransformation

Hepatic.

absorption

Rapidly absorbed (high lipid solubility).

half life

Although no studies have been performed on humans, the half-life in cats is 14.3 hours.