Safety evaluation of pantethine has been made by acute and chronic toxicity tests. In the acute toxicity test, pantethie was administered to mice and rats by various routes. LD_<50> values of pantethine were very high both in mice and rats. In the chronic toxicity test, 4 to 18,000 mg/kg/day of pantethine was given orally to rats for six months. In dose of 80 mg/kg or less, the general condition, weight gain, food intake, hematologic determination, gross and microscopic findings did not suggest the occurrence of drug-related abnormalities. No significant change was found except the slight inhibition of weight gain even at a dose level of 800 mg/kg. Death of the animals due to diarrhea and malnutrition was observed both in doses of 8,000 and 18,000 mg/kg.
