Abstract: Objective To investigate the toxicity of Guishaozichuan granules (GSZC) in SD rats following single-dose and 26-week repeated-dose administration in order to provide a reference for clinical safety evaluation and adverse reaction monitoring. Methods Single-dose toxicity study: Rats were randomized into control and GSZC groups. The GSZC group received the maximum feasible dose (0.47 g herbal powder·mL^-1, 2 mL·100 g^-1, total dose 139.12 g (herbal medicine)·kg^-1) via oral gavage twice within 24 h, while controls received an equivalent volume of purified water. Toxicity symptoms, body weight, feed consumption, and histopathology were monitored for 14 days. Repeated-dose toxicity study: Rats were divided into control and GSZC high-, medium-, and low-dose groups (2 mL·100 g^-1) that were subjected to 26 weeks of continuous administration followed by a 4-week recovery period. Parameters for detection included clinical observations, body weight, hematological, biochemical, and coagulation parameters, organ coefficients, and histopathology. Results Single-dose study: The maximum tolerated dose exceeded 139.12 g·kg^-1 with no significant toxicity. Repeated-dose study: The no-observed-adverse-effect level was 16.3 g·kg^-1. Reversible alterations in hematological/biochemical parameters were observed at higher doses, warranting clinical monitoring. Conclusion GSZC may demonstrate no significant toxicities at clinically adopted doses and within the course of treatment in SD rats.

Key words: Guishaozichuan Granules, Single-Dose Toxicity, Repeated-Dose Toxicity, Safety Evaluation, SD Rats