Aqueous extract of unripe Carica papaya is consumed by some sickle cell patients for its antisickling activities in some parts of southern Nigeria without considering its safety. The effects of the extract on functions of the liver, kidney and bone marrow were investigated in 30 wistar albino rats. The rats were in 6 groups of 5 animals per group. The first group is the control and the other five groups were the study groups. The oral acute toxicity of the extract (LD₅₀) was determined, different doses, 50, 100, 150, 200 and 250 mg/kg were administered daily to the study groups (A, B, C, D, E) respectively for 6 weeks. Liver, kidney and bone marrow function tests were assessed using standard techniques. The results obtained for biochemical and haematological parameters for the control and experimental groups showed no statistical significant different (P>0.05). This result showed that the intake of unripe C.  papaya extract had no adverse effects on the functions of these organs in rats.

Key words: Carica papaya, aqueous extract, liver, kidney, bone marrow, antisickling.