The relationship between buspirone bioavailability and dose in healthy subjects.

Dose dependency of the pharmacokinetics of buspirone, a new anxiolytic agent, was tested in 24 healthy volunteers. Each subject received 10, 20, and 40 mg doses according to a randomized, three-way crossover design with a 7-day interval between treatments. Buspirone AUC values at 10, 20, and 40 mg doses were in the ratio of 1:1.7:3.5 while Cmax values had a ratio of 1:1.9:3.7. The dose normalized (10 mg basis) AUC and Cmax values, Tmax values, and half-lives were not significantly different (p greater than 0.05) among the doses. Buspirone half-life did not change as a function of dose (mg kg-1). It was concluded that buspirone exhibits linear pharmacokinetics following doses in the therapeutic range.