The most powerful topical anti-inflammatory: the cautionary and enlightening story of SKIN-CAP

Topical treatment with glucocorticosteroids is a mainstay therapy for many dermatologic conditions. Though efficacious in many, topical therapies often fail to achieve desired positive results in clinical practice. SKIN-CAP spray (Cheminova Laboratories International SA, Madrid, Spain), a product containing activated zinc pyrithione, and subsequently found to have contained clobetasol, provided unprecedented clearing of psoriasis even when ultra-high potency topical glucocorticosteroids had failed. A PubMed for terms related to corticosteroids, topical therapy, patient adherence, and SKIN-CAP spray was performed. Articles from 1997 to 2023 were included in the review of SKIN-CAP spray. In this review, we report the background of SKIN-CAP as well as studies that were performed in an attempt to explain its perceived high efficacy. The remarkable efficacy that occurred with SKIN-CAP over other delivery systems for high potency topical corticosteroids was initially speculated to be a consequence of an interaction between the zinc pyrithione and the clobetasol. However, no synergistic efficacy was identified, and there was no greater drug delivery. Better adherence to the SKIN-CAP product may explain the efficacy. The SKIN-CAP story provides insights into the need for healthy skepticism, the importance of treatment adherence, and ways to encourage better adherence to topical medications.