ABSTRACT
Alcohol and a variety of street and prescription drugs in the categories of sedatives, hypnotics, and sleeping medications are the most commonly abused substances in North America if tobacco and caffeine-containing beverages are excluded. The group contains alcohol, barbiturates, benzodiazepines, and a few other agents. All of these substances show tolerance, cross-tolerance, and withdrawal syndromes. All act on the GABA benzodiazepine chloride ionophore, but they do not have the same specificity of reaction with this membrane receptor isolated from different parts of the brain. Bromide, largely unavailable in the United States for the last three decades, was a frequently abused, over-the-counter member of this group, delaying the entry of chloride by a slightly different interference.
