Twenty- five albino rats randomly assigned to five groups of five rats each were administered by gavage distilled water and 100, 200, 400 and 800 mg/kg body weight of Hymenocardia acida daily for 28 days. The animals were observed daily for signs of toxicity. At the end of the experimental period, hematological and biochemical parameters were determined. White blood cell count was significantly higher (P < 0.05) in the control than in the group that received 800 mg/kg body weight. All other hematological parameters, except monocytes were unaltered in all the groups. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and urea were found to be higher (P < 0.05) in the treatment groups compared to the control. Treatment-related congestion of the liver was also observed. We conclude that oral administration of aqueous ethanolic extract of H. acida stem bark at the test doses for 28 days is relatively safe.
