Repeated-dose (28 days) oral toxicity study in rats of an antiacne formula (BC-AF) derived from plants

To evaluate the safety of a formula (BC-AF) consisting of the extracts of danshen (Salvia miltiorrhiza), loquat leaf (Glycyrrhiza uralensis), and licorice (Eriobotrya japonica), a preliminary 28-day, repeated-dose oral toxicity study was performed in Sprague-Dawley rats. Eighty animals were divided into four groups, with each group comprising 10 male and 10 female rats. BC-AF was administered once-daily by oral gavage at doses of 0 (control), 2.5 (low), 5 (middle), and 10 (high) g/kg body weight successively for each group for 28 days, respectively. Rats in all groups were sacrificed on day 29, except half of the males and females in the high-dose group that were kept for an additional 2 weeks to observe any possible toxicity after drug withdrawal. In 4 weeks, there were no toxicity reactions or abnormal deaths in any animal groups. There was no significant difference, in comparison to the control group, in clinical signs, organ weights, hematological and serological parameters, or histopathologic findings. In conclusion, the 28-day repeated-dose oral toxicity study demonstrates that BC-AF produced no effects in either male or female rats following oral administration of up to 10 g/kg.