AIMThis study aimed to evaluate the preclinical safety of Shenfu injection for the treatment of sepsis. Tests were designed and conducted to determine the acute and long-term toxicity of Shenfu injection in rats, based on the recommended indications and dosage for human use.MATERIALS AND METHODSRats were administered 22.5 g of raw drug/kg/day via tail vein injection. Toxicity symptoms were monitored for 14 days following the intravenous injection of Shenfu injection, and target organs affected by toxicity were analyzed. To assess long-term toxicity, rats were given 12, 9, or 6 g of raw drug/kg/day by intraperitoneal injection, equivalent to 12, 9, and 6 times the daily clinical dose for adult sepsis patients (3.3 mL of stock solution per 1 g of raw drug/kg/day), for 30 consecutive days. This was followed by a 28-day recovery period after withdrawal of the drug. During the administration and recovery periods, signs of toxicity were observed and compared with those in the control (stromal fluid) group. The aim was to predict potential clinical adverse reactions, including the nature and severity of these reactions, dose-response and time-response relationships, and the reversibility of the effects. Additionally, the study sought to identify the target organs or tissues potentially affected by repeated administration and suggest clinical indicators that should be monitored during the product's use. Furthermore, the safety of co-administration with commonly used chemical medications for the treatment of sepsis was investigated.RESULTSIn the acute toxicity test, administration of the maximum dose of Shenfu injection (75 mL of stock solution/22.5 g of raw drug/kg/day) via tail vein injection resulted in transient symptoms, including piloerection (vertical hair response), weight loss, and reduced food intake. In the long-term toxicity experiments, rats received intraperitoneal injections of 0.3 g/mL (stock solution), 0.225 g/mL, and 0.15 g/mL Shenfu injection per day, which corresponded to 12, 9, and 6 times the daily clinical dose for adults with sepsis. The injections were administered twice daily for 30 days, followed by a 28-day drug withdrawal period for recovery. After 28 days, no significant toxicological changes were observed, apart from a hemodilution effect caused by the excessive volume of the drug and a slight increase in alkaline phosphatase and total bilirubin levels. The effects were reversible upon drug discontinuation.CONCLUSIONSA single intravenous injection of 22.5 g of raw drug/kg/day and long-term intraperitoneal administration of up to 12 g of raw drug/kg/day are considered safe doses for rats.