Buspirone blocks motion sickness and xylazine-induced emesis in the cat

The ability of buspirone to prevent motion sickness and the mechanism of the buspirone action were tested in cats pretreated (s.c. injection) by buspirone 30 min before being subjected to motion stimulus (in a device described by Crampton and Lucot, 1985) or to an injection of an emetic drug xylazine (using only cats susceptible to motion sickness or to xylazine, respectively). Buspirone treatment was found to block motion sickness with an effective dose-50 of 0.46 mg/kg. Buspirone pretreatment (with 4.0 mg/kg) has also significantly blocked vomiting in cats later injected with 0.66 mg/kg xylazine. The results indicate that buspirone is acting at the vomiting center, the point of convergence for the separate mechanisms subserving chemically-induced emesis and motion sickness.