Toxicity of a novel anti-tumor agent 20(S)-ginsenoside Rg3: A 26-week intramuscular repeated administration study in rats

► In this communication, the potential subchronic toxicity of Rg3 was investigated. ► A 26-week intramuscular toxicity study in rats was conducted. ► Rg3 was administrated to rats at dose levels of 0, 4.2, 10.0 or 20.0mg/kg/day. ► The no-observed-adverse-effect levels for rats were considered to be 4.2mg/kg/day. The purpose of this study is to investigate the potential subchronic toxicity of 20(S)- Ginsenoside Rg3(Rg3), by a 26-week repeated intramuscular administration in rats. Rg3 was administrated to rats at dose levels of 0, 4.2, 10.0 or 20.0mg/kg/day. There was no treatment-related mortality and, at the scheduled autopsy, dose-dependent increases in the absolute and relative spleen weights, of both the 10.0mg/kg and 20.0mg/kg dose groups were observed. Absolute and relative kidney weights were significantly elevated in the female 10.0mg/kg dose group and in the male 20.0mg/kg dose group. Hematological investigations revealed a dose-dependent increase in the total white blood cell (WBC) count and in the percentage of neutrophils, but a decrease in the percentage of lymphocytes, in rats treated with doses of 10.0/20.0mg/kg. These effects were completely reversible during the recovery period, and no other adverse effects were observed. It was concluded that the 26-week repeated intramuscular dose of Rg3 caused increases in the spleen and kidney weights, WBC counts and in the percentage of neutrophils, but a decrease in the percentage of lymphocytes, with doses of 10.0 or 20.0mg/kg/day. The no-observed-adverse-effect level for rats was considered to be 4.2mg/kg/day.