Subchronic toxicity studies of Radix Astragali extract in rats and dogs.

Radix Astragali extract (RAE) is obtained from Astragalus membranaceus. It consists of Astragalus polysaccharide and Astragalus membranaceus saponins. In the study, we observed the subchronic toxicity of RAE in Sprague-Dawley rats and beagle dogs to evaluate the safety dosage range in clinical application. These subjects were daily administered of RAE by intra-peritoneum or vein for three consecutive months. General index were observed such as food-intake, behavior, body weight, hematological parameters, etc. Body weight, the weight of principal organ and hematology index are normal in experimental groups and control groups. The hematological biochemistry examination and histopathology examination of experimental groups are similar to control groups. In conclusion, our studies clearly demonstrated that RAE was safe without any distinct toxicity and side effects, the safety dosage range is 5.7-39.9g/kg for rats and 2.85-19.95g/kg for beagle dogs, which is equal to 70 or 35 times of that of human (0.57g/kg, say, average BW 70kg), respectively.