To relieve the dryness of atopic dermatitis skin, a lipid formulation of fusidic acid and betamethasone 17-valerate (Fucicort Lipid cream) was developed as an additional treatment option to the established Fucicort cream. The two formulations were compared in patients with clinically infected atopic dermatitis. A total of 629 patients were randomized to twice daily double-blind treatment for 2 weeks with either Fucicort Lipid cream, Fucicort cream, or the new lipid cream vehicle. Clinical assessment was based on a Total Severity Score of the eczematous lesions. Bacteriological samples were taken at inclusion and at subsequent visit(s) if clinically infected lesions persisted. At the end of treatment, the mean reduction in Total Severity score was 82.9% in the lipid cream group, 82.7% in the cream group, and 33.0% in the vehicle group. The percentage of patients with a successful bacteriological response was 89.7%, 89.6% and 25.0%, respectively. Thus, the clinical and anti-bacterial effect of the lipid cream was found to be similar to that of the established cream formulation, and significantly better than that of the vehicle. The new lipid formulation, therefore, offers an efficient, safe and well-tolerated alternative for the short-term treatment of clinically infected atopic dermatitis.