COMPARISON OF A TOPICAL BENZOYL PEROXIDE GEL, ORAL MINOCYCLINE, ORAL DOXYCYCLINE AND A COMBINATION FOR SUPPRESSION OF P-ACNES IN ACNE PATIENTS

Four groups of ten acne patients each received one of the following tr eatments for 1 month: (1) minocycline-'D', 100 mg twice daily; (2) dox ycycline monohydrate, 100 mg twice daily; (3) 6% benzoyl peroxide-zinc gel twice daily; (4) minocycline-'D', 100 mg twice daily and 6% benzo yl peroxide-zinc gel twice daily Suppression of Propionibacterium acne s was assessed by the detergent scrub method after 2 and 4 weeks of tr eatment. Minocycline-'D' had a far greater ability to suppress P. acne s than doxycycline. Minocycline-'D' resulted in almost a 2-log decreas e in P. acnes compared with less than 1-log decrease with doxycycline, Benzoyl peroxide-zinc gel was also more efficacious than doxy-cycline , As expected, the combination of minocycline-'D' and benzoyl peroxide -zinc gel was substantially more effective than the comparator treatme nts. The greater therapeutic efficacy of minocycline-'D' in acne canno t be fully explained by its antibacterial activity. Evidence is presen ted to show that minocycline has a wide spectrum of pharmacologic acti vities, including antiinflammatory effects, which explains its increas ing therapeutic applications in a variety of unrelated disorders.