Ninety-six HIV-infected infants and children who are intolerant to trimethoprim / sulfamethoxazole ( TMP / SMX ) are randomized to receive oral dapsone in a lower dose once daily or at a higher dose once weekly. Treatment continues until the last patient enrolled has received at least 3 months of therapy. Blood samples are drawn between weeks 4 and 8, at weeks 12 and 24, and every 3 months thereafter during dapsone administration.