Treatment of acute gonococcal urethritis in men with simultaneous infection with Chlamydia trachomatis.

Each of 201 men with symptoms and signs of acute urethritis was randomly assigned to one of two treatment regimens: ampicillin (2g) plus probenecid (1g), or sulphamethoxazole-trimethoprim (SMX-TMP) (sulphamethoxazole 1600 mg plus trimethoprim 320 mg) four tablets twice daily for two days. Before treatment Neisseria gonorrhoeae was isolated from 162 patients, while coexistent Chlamydia trachomatis was recovered from 42 (26%) men. After treatment N gonorrhoeae persisted in 11 (14.3%) of the 77 patients treated with ampicillin and probenecid and in three (3.5%) of the 85 treated with SMX-TMP (p less than 0.05), while C trachomatis persisted in four (16%) of the 25 men treated with SMX-TMP and in all 17 patients treated with ampicillin and probenecid. SMX-TMP was thus more effective than ampicillin in treating acute gonorrhoea in men and in eradicating concurrent C trachomatis infection.