BACKGROUND: The bacteriological implications of treating eczema infected with Staphylococcus aureus with topical betamethasone/fusidic acid have been reviewed. METHODS: A retrospective review and analysis of results from 8 previously conducted clinical studies was performed. RESULTS: Overall, bacteriological efficacy was recorded in 326 (89.6%) of the 364 patients assessed, In comparative studies, bacteriological efficacy was 86.0% for betamethasone/neomycin (n.s.), 85.4% for betamethasone/gentamicin (n.s.), 69.6% for betamethasone/clio-quinol (P = 0.04), 70.4% for betamethasone (P < 0.01) and 25.0% for an ointment vehicle (p < 0.001), The emergence of fusidic acid-resistant strains of S. aureus was seen in nine (2.8%) patients given betamethasone/fusidic acid and in six (2.5%) patients given comparator treatment, CONCLUSION: When betamethasone/fusidic acid treatment is given for short periods there is little selection pressure on the development of resistance to fusidic acid.