Ninety paucibacillary leprosy patients having indeterminate (I), tuberculoid (TT) and borderline tuberculoid (BT) type of leprosy with bacterial index (BI) of less than two on the Ridley scale were treated with rifampicin (RFM) 600 mg once a month, dapsone (DDS) 100 mg daily and prothionamide (PTH) 250 mg daily. Treatment was stopped at the end of six months. The patients tolerated the drugs fairly well and in only two patients the drugs had to be stopped (in one due to jaundice and in the other due to gastric intolerance). About 6% of patients had early reactions which subsided with additional steroid therapy. The inactivity rate was 60% at six months and this improved to 96% at 12 months. No cases of late reactions and relapses were encountered in the limited follow-up period of six months; and a longer follow-up is necessary for ascertaining the relapse rates. The preliminary results however suggest that the addition of prothionamide to the standard WHO paucibacillary regimen is well-tolerated with increased inactivity rate and fewer instances of late reactions.