Glucocorticoids exert valuable therapeutic activities in skin infections, although their use is limited by the occurrence of undesiderable effects: glucocorticoids depress the local defence mechanisms and, in low concentrations, stimulate microbial metabolism. For these reasons, combined preparations containing an antimicrobial substance besides the glucocorticoid are recommended. However, interactions between the steroids and the antimicrobials must be ruled out beforehand, i.e. the unimpaired activity of both steroid and antimicrobial must be assured. Examples of such investigations are reported for the most widely used compounds for topical therapy. The simultaneous use of a glucocorticoid and an antimicrobial is not recommended in only a few instances.