Acute and subchronic toxicity assessment of the hydroalcoholic extract of Stachys lavandulifolia in mice.

Stachys lavandulifolia is used as the herbal tea and its wide and potent medical effects have been reported for the extract in animal studies. This study aimed to find the safety profile of the extract to find the appropriate doses for further human studies. The aerial parts of the plant were air-dried and the hydroalcoholic extract was obtained and concentrated by percolation method with 140 mg/ml concentration. To assess the toxicity profile of this extract, 60 female mice (30 cases, 30 controls, 24.8 ± 2.1 g, 4-6 weeks) were administered the extract by oral gavages in acute (24 hrs), subacute (14 days) and subchronic (45 days) models. All clinical, hematological, biochemical and histopathological changes were assessed in appropriate midpoints and endpoints and compared with control group. Doses up to 140 mg⁄kg were recognized as maximum tolerated dose in subchronic model. Abnormal changes in kidney and liver weight in treatment groups as well as the significant elevation of biochemical parameters in 45 days study has suggested the possible hepatic and renal toxicity potentials of this extract with doses upper than 140 mg⁄kg. Doses up 70 mg⁄kg could be considered as no observable adverse effect level (NOAEL) and could be used in further clinical trials on the possible therapeutic effects of this plant.