Investigation of the abuse liability of buspirone in alcohol-dependent patients

By use of the Addiction Research Center Inventory, the Amphetamine Self-Rating Scale, the Single-Dose Questionnaire, and selected physiologic measures (blood pressure, pulse and respiratory rates, oral temperature, and pupil diameter), the abuse liability of buspirone (10, 20, and 40 mg) was compared with that of diazepam (10 and 20 mg) and placebo in 19 subjects who were hospitalized for the treatment of alcohol dependency. Each treatment was given as a single dose at intervals of at least three days according to a double-blind, six-period, crossover Latin square design. Neither buspirone nor diazepam had any effect on blood pressure, pulse and respiratory rates, or body temperature. A small, transient pupillary constriction was evident in the 20- and 40-mg buspirone groups, but it dissipated within two hours after dosing. Both buspirone and diazepam had only a small stimulating effect on appetite. On the Pentobarbital-Chlorpromazine-Alcohol Group and Sedation subscales of the Addiction Research Center Inventory, the 40-mg dose of buspirone yielded effects suggestive of a mild sedative-type drug. Only the 20-mg dose produced a significant effect on the Euphoria scale. Diazepam appeared to be more active as a sedative-hypnotic type of drug, by virtue of its effects on both the Amphetamine and Euphoria subscales and its greater effects on the Morphine-Benzedrine Group, Pentobarbital-Chlorpromazine-Alcohol Group, and Sedation subscales, suggesting euphoria. Not only does the lack of effect of buspirone on the Amphetamine and Morphine-Benzedrine Group subscales indicate lack of a euphorigenic property, but the score on the Lysergic Acid Diethylamide subscale, especially in the 40-mg group, suggests a dysphorigenic property at high doses. On the Amphetamine Self-Rating Scale, buspirone and diazepam affected only the sleep factor and only the 40-mg buspirone dose was distinguishable from placebo. On the Single-Dose Questionnaire, both buspirone and diazepam tended to be rated more as sedative-type drugs, but buspirone was generally less well liked than diazepam. Overall, the results, which suggest a lack of euphoria and the presence of dysphoria at high doses, indicate that buspirone has only limited, if any, abuse liability.