Abstract: Objective To observe the long-term toxicity and severity occurred after administration of Penyanxiao enema in rats. Methods SD rats were randomly divided into 4 groups. Each group was given Penyanxiao enema at dose of 50g·kg^-1、25g·kg^-1 and 12.5g·kg^-1 daily for up to 12 weeks, respectively. Blank control group was given same bulk of distilled water. After the withdrawal of the drug for 2 weeks the rats' body weight, food intake, hematology, blood biochemistry analysis and organ coefficients were measured, and the histopathological changes were also observed. Results The outer appearance and behavior, body weights, organ coefficients, the indexes of hemstology and biochemistry analysis in rats of drug taking groups showed no significant difference from those of control group. Pathological examination discovered no obvious pathological changes related to drug toxicity and no delayed toxicity reaction after drug withdrawal. Conclusion Penyanxiao enema had no obvious toxicity in rats for long-term administration.

Key words: Penyanxiao enema, rats, long-term toxicity