Current usefulness of procaine penicillin in the treatment of pneumococcal pneumonia.

The aim of this study was to determine whether procaine penicillin could be used in the treatment of suspected pneumococcal pneumonia of mild to moderate severity in an area with a high prevalence of penicillin resistance. Forty-nine patients were treated with 1.2 x 10(6) U of i.m. procaine penicillin every 12 h. By intent-to-treat analysis, 40 of 49 patients were cured and no patient died. Streptococcus pneumoniae could be demonstrated in 17 patients; 5 of 17 isolates were resistant to penicillin (MICs 0.25-4 microg/ml). Fifteen of 17 patients were cured with procaine penicillin, one presented allergy, and one was a therapeutic failure. Mean penicillin serum levels were 2.39 +/- 1.16 microg/ml (peak) and 0.61 +/- 0.38 microg/ml (trough). The results suggest that procaine penicillin may still be useful in the empirical therapy of suspected pneumococcal pneumonia.