Background and objectives: Single dose regimens have advantages in the treatment of STD. Azithromycin has unique pharmacokinetics that may make single dose regimens feasible. Treatment with a single 1 g dose of azithromycin was compared to 100 mg doxycycline twice daily for seven days.
Study design: This was a randomized third-party blinded study on 183 male patients, 176 of whom could be evaluated for efficacy.
Results: Chlamydia trachomatis was cultured from 148 patients, 79 receiving azithromycin and 69 receiving doxycycline. Six patients receiving azithromycin had positive cultures on follow-up, four were known to have had sexual intercourse with infected partners. Fifty-one patients had gonorrhea; 28 were treated with azithromycin and 23 with doxycycline. Neisseria gonorrhoeae was eradicated from all patients except one receiving azithromycin. He denied sexual exposure during follow-up. Sixty patients were infected with Ureaplasma urealyticum, 35 were treated with azithromycin and 25 with doxycycline. Five patients in each group had positive cultures on follow up. Three patients receiving azithromycin and two receiving doxycycline were known to have had sexual exposure during follow-up.
Conclusion: A single dose of azithromycin showed similar effectiveness as a 7-day regimen of doxycycline.