Response of Dapsone in Refractory Chronic Immune Thrombocytopenia.

This was a prospective study. A total number of 19 patients with chronic ITP with platelet count <50×10⁸/L, treated with dapsone at a dose of 100 mg/day for nine months and followed up to 12 months were included in this study. Among them 13 patients (76.5%) were responded well shortly to dapsone which persisted during Dapsone therapy. Response rate of Dapsone was declining after Dapsone therapy. Response persisted in 6 patients (35.3%) after stoppage of dapsone up to last follow up at 1 year. Mean platelets count during Dapsone therapy was 168.35×10⁸/L. Shorter duration of thrombocypenic patients were responded well. Except one all patients experienced mild to moderate anaemia. Mean fall of Haemoglobin was 1.4gm/dl during dapsone therapy observed which come back to normal shortly after stoppage of dapsone. Only 2 patients were suffered from moderate anaemia. Dapsone syndrome and methemoglobinamia caused permanent discontinuation of therapy in 2 patients (10.5%) which was revert back to normal shortly after stoppage of drug. This study demonstrates that dapsone is an effective, inexpensive and well tolerated treatment for chronic, refractory ITP.