Comparison of azithromycin and doxycycline in the treatment of non-gonococcal urethritis in men.

Azithromycin has activity in vitro against Chlamydia trachomatis, and its novel pharmacokinetics suggest that even single doses may be effective in the treatment of non-gonococcal urethritis (NGU). This study compared the efficacy and safety of a single 1 g oral dose of azithromycin versus doxycycline 100 mg bid for seven days in the treatment of NGU. Men with symptoms and/or signs of NGU, and with > or = 5 polymorphonuclear leucocytes/high-power field in a Gram's-stained urethral smear, were recruited. Investigations included endourethral swabs for C. trachomatis cell culture. Patients were randomized to receive azithromycin or doxycycline, and were re-assessed on day 7-10 and on day 14-21. Of the 143 men recruited, C. trachomatis was isolated from 51 (40%) of the 128 evaluable patients. Both treatments were well tolerated and had comparable cure rates. Azithromycin 1 g appears to be an effective and safe alternative to doxycycline for the treatment of chlamydial and non-chlamydial urethritis, and its single-dose administration is an advantage in terms of patient compliance.