Methanolic extracts of Costus afer stem was evaluated against paracetamol (800 mg/kg b.w. i.p.) induced tissue injury in rats. The administration of paracetamol caused significant elevations in the levels of serum transaminases, alkaline phosphatase, urea and creatinine. The levels of thiobarbituric acid reactive species in both liver and kidney also increased over control (P < 0.05). Rats pre-treated with Costus afer extract (p.o.) at 200 mg/kg body weight and 400 mg/kg body weight before paracetamol was administered however, resulted to a significant reduction of the markers that were raised (P < 0.05). Rats pre-treated with the 400 mg/kg b.w. of the extract before the administration of paracetamol showed greater reductions in the levels of the markers close to control levels in some cases. This indicated that Costus afer possesses the ability to protect the tissues against paracetamol-induced injury. This could probably be due to the presence of antioxidant phytochemicals that work in synergy.

Keywords: Costus afer, paracetamol, urea, creatinine, antioxidant