Comparison of therapeutic effects of oral doxycycline and azithromycin in patients with moderate acne vulgaris: What is the role of age?

BACKGROUND

Acne vulgaris is the most common dermatological disorder in adolescence and young adults. In past decades, systemic antibiotics have had the main role in the treatment of acne patients with inflammatory papules and cysts. They are sometimes associated with side effects, contributing to reduced compliance.

OBJECTIVE

This study aimed at comparing the efficacy and safety of oral azithromycin and doxycycline in the treatment of moderate acne vulgaris, considering the age of patients as an influencing parameter.

METHODS

In a randomized, double-blind, clinical trial, 100 patients with moderate acne vulgaris who attended the outpatient dermatology clinic were evaluated during a 15-month period. They were randomized into two equal groups: A and D. Patients in group A received oral azithromycin (500 mg daily, 4 consecutive days per month for 3 consecutive months) and patients in group D took doxycycline (100 mg daily for 3 consecutive months). The number and types of lesions (all over the body) were determined at baseline and at the end of each month for 90 days afterwards. Michaelson's acne severity score was also determined at baseline and at the end of the third month after initiating treatment. Patients were followed up for another 3 months after discontinuation of treatment to determine the recurrence rate.

RESULTS

Both antibiotics were comparably effective in the treatment of moderate acne vulgaris. There was no significant side effect in the A group and the complications were minor in the D group. Doxycycline was significantly more effective in patients older than 18 years.

CONCLUSION

Azithromycin is at least as effective as doxycycline in the treatment of moderate acne vulgaris; however, in patients older than 18 years doxycycline is better.