Pentylenetetrazol (PTZ)-induced oxidative stress results in disturbance of the antioxidant enzyme status accompanied by neuronal injury and the development of epilepsy in rats. The present study evaluated the antioxidant effects of curcumin against PTZ-induced convulsions. Over a period of 30 days, i.p. injections of subconvulsive doses of PTZ on alternate days resulted in the development of a well-known kindling model of epilepsy. Spectrophotometric analysis revealed a markedly elevated activity of the antioxidant enzymes malondialdehyde (MDA), catalase and glutathione S-transferase (GST) in the cerebrum and cerebellum of epileptic rats due to PTZ-induced oxidative stress. Oral supplementation of curcumin at a dose of 2 g/kg for 30 days resulted in a transient decrease in MDA, catalase and GST levels in the rat cerebrum and cerebellum. Piperine (20 mg/kg orally) was administered along with curcumin to enhance the bioavailability of the latter up to 20-fold more. Combined treatment with curcumin and carbamazepine (3.6 mg/kg orally) also gave similar results, indicating that the potent antioxidant curcumin can be used as an adjuvant in antiepileptic therapy.