Abstract We tested the ability of dapsone (4,4′-diamino-diphenyl sulfone) to attenuate kainic acid-induced seizures. We observed that 9.375 and 12.5 mg/kg doses of dapsone administered 30 min before a single kainic acid (10 mg/kg) i.p. injection were able to decrease the time of electroencephalographic seizures by 52% and 82%, respectively, as compared with rats administered with 10 mg/kg kainic acid only. The 12.5 mg/kg dose of dapsone was also able to diminish both kainic acid-evoked body and head shakes (58%) and kainic acid-induced mortality (75%). These results suggest that dapsone could be used in clinical trials as anticonvulsant.