SHIN ATROPHY INDUCED BY INITIAL CONTINUOUS TOPICAL APPLICATION OF CLOBETASOL FOLLOWED BY INTERMITTENT APPLICATION

Background: The most frequent side effect of a long-term topical corti costeroid therapy is skin atrophy. To avoid or to reduce atrophy often an initial continuous application is followed by an intermittent main tenance therapy. Objective: In this study we measured the skin thickne ss before and after the two-phase application schedule with the superp otent topical steroid clobetasol propionate (CP). For 16 days CP sampl es were applied twice daily on the test areas of 12 volunteers (phase 1). Then CP was applied to the same skin areas in accordance with the following timing: every 5th day, every 7th day, every 10th day, every 14th day (phase 2). Phase 2 lasted for 45 days. During the entire peri od of the study the skin thickness was measured regularly by the skin compression and thickness method as described previously. Results: It could be seen that in phase 1 the skin became about 15% thinner. In ph ase 2 the steroid-induced skin thinning was approximately the same whe n CP was applied every 5th or 7th day. The skin thickness reached a mo re or less normal level when CP was applied every 10th day. After the 14th day a completely normal lever was found. By measuring the skin th ickness every day it was further shown that the skin thinning process lasted for 3 days when CP was applied once only. Conclusion: These res ults demonstrate that skin thinning must be expected by an intermitten t maintenance therapy applied at relatively short intervals. The longe r the intervals, the weaker the skin thinning. Moreover, these investi gations showed that the skin thinning effect after a single CP applica tion persists for nearly 3 days.