In this investigation skin fold thinning was determined after topical application of several potent corticosteroids in hairless mice using a simple mechanical measuring device. The skin thinning effect of prednicarbate was compared with other corticosteroids (amcinonide, β-methasone-17-valerate, clobetasol-17-propionate, diflorasone-17,21 -diacetate, hydrocortisone-21 -acetate). Prednicarbate produced a clear thinning of skin. Like other tested dermatocorticoids prednicarbate caused a significant atrophy of the mouse tail epidermis. By prednicarbate the 3H-thymidine triphosphate incorporation into epidermal DNA was inhibited.