Meprobamate was introduced as an antianxiety agent in 1955 and is prescribed primarily to treat anxiety, tension and associated muscle spasms. More than 50 tons are distributed annually in the United States under its generic name and brand names such as Miltown and Equanil. Its onset and duration of action are similar to the intermediate-acting barbiturates; however, therapeutic doses of meprobamate produce less sedation and toxicity than barbiturates. Excessive use can result in psychological and physical dependence.