Efficacy of treatment regimens for lower urogenital Chlamydia trachomatis infection in women.

One hundred thirteen women had Chlamydia trachomatis isolated from the cervix, or urethra, or both, were treated, and followed until failure occurred or for at least 40 days after initiation of treatment. On regimens given four times daily for 7 days, failure occurred in three (8%) of 38 on tetracycline, 500 mg, in none of five on erythromycin, 500 mg, and in three (8%) of 37 on erythromycin, 250 mg. On regimens of 500 mg given four times daily for 10 days, failure occurred in none of nine on tetracycline and in one (4%) of 24 on sulfisoxazole. Erythromycin, 500 mg, was stopped because of severe side effects. Another 10 women were given a loading dose of ampicillin plus additional ampicillin for 3 to 21 days and were followed for 4 to 76 days after treatment was stopped. Only two women remained culture positive after therapy. This study demonstrates that antimicrobial regimens that are frequently given to women in North America have significant activity against C. trachomatis.