Trimethoprim-sulfamethoxazole versus aerosolized pentamidine for primary prophylaxis of Pneumocystis carinii pneumonia: a prospective, randomized controlled clinical trial

Trimethoprim-sulfamethoxazole (TMP-SMX) appears to be as effective as pentamidine aerosol in preventing Pneumocystis carinii pneumonia (PCP), but side effects may be a drawback. PCP is a lung disease that often occurs in patients with HIV infection or AIDS. Of 214 HIV-infected patients who had never had PCP, 106 received pentamidine treatment and 108 received TMP-SMX. The pentamidine was administered by aerosol, one treatment per month. The TMP-SMX was taken as a daily pill. The patients were followed for an average 578 days. Only two patients taking TMP-SMX developed PCP, compared with five being treated with pentamidine. However, 33 patients in the TMP-SMX group experienced moderate to severe side effects and were switched to the other group. Only five patients in the pentamidine group were switched because of side effects. Survival rates were similar in the two groups. The lower cost of TMP-SMX may contribute to its use as an alternative to pentamidine in preventing PCP.