Dapsone is an antibiotic medication most commonly used for the treatment of Mycobacterium leprae infections (leprosy). Dapsone can also be used to treat dermatitis herpetiformis and other skin conditions. It is also sometimes used to prevent Pneumocystis carinii pneumonia (PCP) in patients with HIV and to treat Idiopathic thrombocytopenic purpura.

Dapsone is administered orally.

The primary side effect of this drug is anemia (hemolytic) and methemoglobinemia, though other side effects, including nausea, headache, and peripheral neuropathy have been known to occur in patients on this medication.