Aristolochia ringens (Vahl) and Securidaca longepedunculata Fresens are used in traditional African medicine for the treatment of arthritis, diarrhoea, asthma, snakebites and skin rashes. This present study examines the acute and sub-acute toxicity effects of these plants in rats. The animals (5 per group) were treated daily with the extract at doses of 100, 250, 500 mg/kg orally for 28 days. Control group received distilled water and all animals were weighed at 7 days interval. The extract showed no significant change in the percentage body weight in a dose-dependent manner as compared to the control. There was no significance difference in the weight of organs in the extract of A. rigens while the extract of S. longepedunculata exhibited a significant dose-dependent decrease in the weight of the liver and heart at all the treated groups (p<0.05) in the 28 day. The haematological and biochemical parameters were determined. Extract significantly increased red blood cell (RBC), haemoglobin (HGB) and haemotocrit (HCT) in A. ringens while it decreased in S. longepedunculata extract in the study. Other haematological parameters (WBC, MCHC, MCV and MCH) of the treated rats were not significantly different when compared to the control rats. All blood serum biochemical parameters were not significantly (p<0.05) different as compared with the control group, except for a significant (p<0.05) non-dose-dependent increase of TP, HDL-c and LDL-c of A. ringens extract. However, the serum levels of Creatine and Alanine transaminase of S. longepedunculata showed a significant non dose-dependent increase compared to the control group. The ethanolic stem and root extract of Aristolochia ringens and Securidaca longepedunculata respectively are safe when administered orally as it is reported in this study to be non toxic in rats.

Keywords: Biochemical; Haemotology; Toxicity; Rats; Aristolochia ringens; Securidaca longepedunculata