Dapsone induced hemolysis and drop in saturation in normal glucose-6-phosphate dehydrogenase level patients – alarming presentation of poor man’s drug: A series of 12 cases and review of literature

Abstract: BACKGROUND: Dapsone-induced hemolysis is well described in the literature, especially in glucose-6-phosphate dehydrogenase (G6PD) enzyme deficiency. However, it is reported rarely with normal G6PD levels. OBJECTIVES: The objective of the study was to describe the association between dapsone and fall in oxygen saturation (SpO 2 ) and hemoglobin after intake of the drug. MATERIALS AND METHODS: All outpatients and inpatients receiving dapsone who presented with breathlessness, fall in SpO 2 , hemolysis, and fall in hemoglobin were included in the study. Patients who were started on dapsone were asked to measure the SpO 2 regularly and observed for any breathlessness. Complete blood count (CBC) and liver function test (LFT) were repeated, and a reticulocyte test was done after 1 week of dapsone. RESULTS: Twelve cases (5 female and 7 male) with a mean age of 47 years, ranging from 22 to 83 years, presented with various dermatological conditions treated with dapsone. SpO 2 fell in all cases, of which eight cases developed breathlessness after starting dapsone. Nine cases developed a reduction in hemoglobin (Hb) with increased reticulocyte counts. The mean decrease in Hb was 2.74 mg/dL. LFT was deranged postdapsone in six cases. Dapsone was stopped in all cases, following which Hb level improved, and there was relief of breathlessness with normal SpO 2 . Confirmation was done by drug provocation with dapsone. CONCLUSION: Baseline CBC and SpO 2 with frequent repetition every week, along with reticulocyte count, are essential to look for dapsone induced hemolysis and methemoglobinemia.