Barbiturates

Synonyms

Central nervous system depressants; Sedative-hypnotics

Definition

Barbiturates belong to a class of medications known as sedative-hypnotics. Initially they were prescribed for their anxiolytic and relaxing properties. Later, they were also used as anticonvulsants, and shorter-acting forms were developed for use as anesthetics in surgery (Feldman et al. 1997).

Barbiturates affect a subtype of the receptors of the neurotransmitter, gamma aminobutyric acid (GABA), one of the most common inhibitory neurotransmitter systems in the brain. Their behavioral effects include relaxation, drowsiness, and feelings of euphoria. However, their widespread effects also result in the depression of reflexes and cardiovascular and respiratory functions, particularly at higher doses (Feldman et al. 1997).

The psychoactive effects of barbiturates increase their risk for drug dependence and abuse. Symptoms of tolerance and withdrawal develop with chronic use. Reportedly, tolerance develops to the...