indication
For the management of anxiety disorders or for the short-term relief of the symptoms of anxiety.
pharmacology
Meprobamate is an anxiolytic drug. It was the best selling minor tranquilizer for a time but has largely been replaced by benzodiazepines. Meprobamate has most of the pharmacological effects and dangers of the barbiturates (though it was marketed as being safer). However, it is less sedating at effective doses. It is reported to have some anticonvulsant properties against absence seizures, but can exacerbate generalized tonic-clonic seizures. It has also been used as a hypnotic (sleeping pill). However, its is currently only licensed as an anxiolytic and it is a third or fourth-order choice.
mechanism of action
Meprobamate's mechanism of action is not known. It has been shown in animal studies to have effects at multiple sites in the central nervous system, including the thalamus and limbic system. Meprobamate binds to GABA
A receptors which interrupt neuronal communication in the reticular formation and spinal cord, causing sedation and altered perception of pain.
toxicity
Symptoms of overdose include coma, drowsiness, loss of muscle control, severely impaired breathing, shock, sluggishness, and unresponsiveness. Death has been reported with ingestion of as little as 12 g meprobamate and survival with as much as 40 g.
biotransformation
Hepatic.
absorption
Well absorbed from the gastrointestinal tract.
half life
Plasma half-life is about 10 hours.