Trimethoprim/sulfamethoxazole (TMP/SMX), which is effective for secondary PCP prophylaxis, is associated with allergic manifestations and side effects that limit its use. Patients who are intolerant of TMP/SMX require an effective alternative. Dapsone and atovaquone have both shown promise as PCP prophylactic agents.~Patients are randomized to receive either dapsone or atovaquone daily, with follow-up at the clinic every 4 months.
To compare the efficacy and safety of dapsone versus atovaquone in preventing or delaying the onset of histologically proven or probable Pneumocystis carinii pneumonia in HIV-infected patients with CD4 counts <= 200 cells/mm3 or <= 15 percent of the total lymphocyte count who are intolerant to trimethoprim and/or sulfonamides.~Trimethoprim/sulfamethoxazole (TMP/SMX), which is effective for secondary PCP prophylaxis, is associated with allergic manifestations and side effects that limit its use. Patients who are intolerant of TMP/SMX require an effective alternative. Dapsone and atovaquone have both shown promise as PCP prophylactic agents.