Tulobuterol: one-month intravenous safety studies in rats and dogs

Tulobuterol was given intravenously to rats and dogs at dosages of 1, 5, or 25 mg/kg/day and 0.6, 2, or 6 mg/kg/day, respectively. The no-toxic-effect dosages were 5 mg/kg/day in rats and 6 mg/kg/day in dogs. Two rats died at 25 mg/kg/day. Convulsions, jerking movements, hyperactivity, tremors, hypoactivity and ptyalism were observed in rats given 25 mg/kg/day. Restlessness, ptyalism and hypoactivity were also observed in dogs at 2 and 6 mg/kg/day. Cutaneous and/or mucosal erythema were observed in rats and dogs at all dosages. Increased body weight gain occurred in drug-treated rats and in mid- and high-dose female dogs. Slight elevations in serum creatinine and BUN were seen in rats and dogs at the highest dosages. Heart weights were increased in rats at all dosages after 1 month of treatment and in rats given 25 mg/kg/day after 2 weeks of recovery. There were no treatment-related morphologic changes in either species.