The safety and anthelmintic activity of the crude aqueous leaf extract of Anogeissus leiocarpus was investigated in sheep naturally infected with gastrointestinal nematodiasis using the feacal egg count reduction test and the controlled test. The results indicate that the extract had no significant (P>0.05) effect on the vital parameters such as temperature, respiratory and pulse rates nor did it produce any sign of toxicity in the treated animals. There were also no significant changes (P>0.05) in the body weight and haematological parameters of the albendazole or extract treated groups except the packed cell volume (PCV) of albendazole treated group and the white blood cells of the 400 mg/kg treated group and untreated group seven days post-treatment, which were significantly higher (P
