[Acute toxicity study of buspirone hydrochloride in mice, rats and dogs]

Buspirone hydrochloride (abbr. to BH), an anxiolytic drug, was examined for its intravenous, subcutaneous or oral acute toxicity using Crj: CD-1 (ICR) mice, Crj: CD (Sprague-Dawley) rats and beagle dogs of both sexes. The results obtained were summarized as follows: 1. Drug-related toxic signs included decreased activity and convulsions accompanied with salivation and opisthotonus in mice and rats treated with BH regardless of administration routes, and tremors and clonic convulsions accompanied with salivation in dogs treated with BH orally. 2. Pathological examinations revealed distention of the stomach in dead rats treated with BH orally, and hypersecretion of gastric juice and alterations (viz. edema, necrosis and petechia) on the superficial mucous membrane in the gastropyloric region in dead dogs treated with BH orally. 3. The cause of death was considered to be due to respiratory insufficiency in every species of animals examined. 4. LD50 values (mg/kg) were as follows: [table: see text] 5. No sex differences were observed in every species of animals regardless of administration routes on the basis of toxicological parameters examined.