In a randomized prospective therapeutic study, 33 patients with perioral dermatitis received a topical erythromycin preparation, 35 received oral tetracycline and 31 received placebo . The treatment response was evaluated by papule count. Oral tetracycline and the topical erythromycin preparation were superior to placebo in achieving a satisfactory therapeutic response (0 to 10 remaining papules) (P < 0.001) and in reducing the number of papules observed at several follow-up visits starting on day 20. The topical erythromycin preparation performed similarly to oral tetracycline.
The twice-daily topical application of 1% metronidazole cream was compared with 250 mg oral tetracycline, taken twice daily, in the treatment of perioral dermatitis in a prospective, double-blind, double-dummy, randomized, multicentre trial in 108 patients treated for 8 weeks . The median number of papules in the metronidazole-treated group was reduced to 8% of the initial number, and the median number in the group treated with tetracycline was reduced to 0% of the initial number. Although both treatments were effective, oral tetracycline was significantly more effective than topical metronidazole.
Comment: The quality of evidence is downgraded by imprecise results (limited study size for each comparison).