Acute and repeated toxicological study of Myelophil, an ethanol extract of a mixture of Astragali Radix and Salviae Miltiorrhizae Radix, in beagle dogs

BACKGROUND: To evaluate the pharmaceutical safety of Myelophil, an ethanol extract of a mixture of Astragali Radix and Salviae Miltiorrhizae Radix, using both acute and repeated toxicological studies. METHODS: A total of 40 beagle dogs (20 each male and female) were fed doses up to 5,000 mg/kg for the acute study and up to 1,250 mg/kg for the 13-week repeated dose toxicological study. Adverse effects were examined intensively by comparing the differences between normal and drug-administered groups using clinical signs, autopsies, histopathological findings, hematology, urinalysis, and biochemical analysis. RESULTS: No mortality or drug-related clinical signs were observed in the Myelophil-treated groups, except for vomiting due to an excessive dose (5,000 mg/kg). Likewise, in the repeated toxicity test, compound-colored stools in the Myelophil-treated groups and soft stools in all groups, including the control, were observed. No drug-related abnormalities were found in the histopathology, hematology, urinalysis, and biochemical analyses for any doses of Myelophil. CONCLUSION: These results support the safety of Myelophil with a no observed adverse effect level (NOAEL) of 1250 mg/kg in beagle dogs, which corresponds to a human equivalent dose (HED) of 694 g/kg. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12906-019-2588-3) contains supplementary material, which is available to authorized users.