Effects of topically applied clobetasol-17-propionate on histamine release in human skin.

The effects of topical glucocorticoid treatment on histamine responses and histamine release induced by the histamine liberating agent compound 48/80 were studied in 17 healthy volunteers. The potent glucocorticoid ointment clobetasol-17-propionate was applied on one upper arm of each individual 14, 4 and 2 hours before testing. The other arm was treated in the same way with the corresponding vehicle. Solutions of histamine and compound 48/80 were injected intradermally in both arms. The size of the flare reaction and the duration of the itch response were recorded. It was found that the flare reactions evoked by histamine were slightly (p less than 0.05) reduced on the steroid-pretreated arm whereas the responses to compound 48/80 were much more suppressed (p less than 0.01). Glucocorticoid treatment did not influence the itch responses to histamine while the itch duration following injection of compound 48/80 was significantly reduced in steroid-treated skin compared to control skin. Our results indicate that topical glucocorticoid treatment can suppress histamine release from dermal mast cells in man.