Prevention of Pneumocystis carinii pneumonia relapse in AIDS patients. The efficacy and tolerability of low-dose sulfamethoxazole-trimethoprim.

The effectiveness and tolerability of Sulfamethoxazole with Trimethoprim (SMX-TMP), a dose of 400mg/80mg given twice a day as secondary prophylaxis (SP) against Pneumocystis carinii pneumonia (PCP) was assessed retrospectively in 166 AIDS patients. The mean observation period was 9.7 months (range 1.0-1.4). Relapse of PCP occurred in eight patients; four episodes were histologically verified and four episodes were clinically assumed. The relapse rate after one year of prophylaxis was 5.1% (95% CI 0.0%-11.0%) using the log-rank test. Intolerance of secondary prophylaxis, defined as adverse effects necessitating cessation of SP with SMX-TMP, was reported in eight patients (5%) (95% CI 2.1%-9.3%).