In a randomized double-blind trial fifty-one patients with rosacea were treated for 2 months with either 1% metronidazole cream and placebo tablets or with 250 mg oxytetracycline tablets taken twice daily, and placebo cream (the cream base). The patients were assessed before and at the end of the trial, using the following criteria: (1) overall clinical assessment, (2) lesion counts, (3) degree of erythema, (4) independent photographic evaluation, (5) patients' opinion. An improvement was shown in 90% of the patients of both groups, and there was no significant difference between the two treatments.

One per cent metronidazole cream has been shown to be significantly better than a placebo cream in the treatment of rosacea (Gamborg Nielsen, 1983a), It was therefore considered important to compare the cream with conventional therapy, and for this reason a double-blind study of 1% metronidazole cream versus a daily dose of 500 mg oxytetracycline was performed.