Aim: The aqueous leaf extract of B. pinnatum (BP) is effective as herbal medicine for hypertension, diabetes and convulsions, for which there has not been reliable subchronic toxicity data. This study aimed to study possible health effects of subchronic use of BP, as a predictor of long-term use in humans. Methods: Acute 24h oral (in mice) and 90 day-subchronic toxicity (in rats) tests were conducted as predictors for human outcome. Following 90 days, and 21 days reversibility tests, biochemical- ALP, ALT and AST, LDH, direct bilirubin, uric acid and creatinine were measured; oxidative stress- CAT, SOD), MDA; and histopathologic parameters were determined. No mortality was recorded up to 5g/kg of BP in acute toxicity test. After 90 days, 1000 mg/kg BP, caused significant, but reversible increases in all ALP, AST, ALT, LDH, uric acid, and creatinine. Results: At 100 & 1000 mg/kg of BP, the MDA was significantly elevated for kidney, heart, lungs and spleen; but at 1000 mg/kg, BP produced significant reduction of CAT and SOD; and elevation of MDA for all organs. These effects on CAT, SOD and MDA, except the lungs at 1000 mg/kg and testes at 100 mg/kg and 1000 mg/kg, were reversed. At 1000 mg/kg BP caused some observable changes in the kidneys and liver of few of the rats, irreversible pathologic changes were observed in the testis. Conclusion: These findings suggest that vital organs toxicities could occur during long-term use of BP, especially for irreversible pathologic changes in the testis.