Dapsone-induced methemoglobinemia in pediatric oncology patients: case examples.

Over the last 25 years, significant advances have been made in supportive care of the immunocompromised patient. One significant advance is the use of trimethoprim-sulfamethoxazole (TMP-SMZ) in the prevention of Pneumocystic carinii pneumonia (PCP). Although TMP-SMZ remains the drug of choice for PCP prophylaxis, children who develop or have a history of adverse reactions must be prescribed an alternative treatment. In these instances, medications such as dapsone, aerosolized pentamidine, or atovaquone are prescribed. This report discusses four children with sulfa allergy who were prescribed dapsone and later developed methemoglobinemia. Although methemoglobinemia is associated with dapsone, there was no reference found regarding this link in the pediatric oncology literature. The purpose of these clinical examples is to alert the pediatric nurse and advanced practitioner to the association of dapsone and methemoglobinemia.