Antipruritic and thermal sensation effects of hydrocortisone creams in human skin

Few studies evaluate the effect of topical corticosteroids on thermal sensa tion and in alleviation of itch produced by intradermal injection of histam ine. We evaluated the antipruritic effect of hydrocortisone (1% and 2.5%) o n histamine-induced itch and sensory effects by measuring itch magnitude, i tch duration and thermal thresholds using a computerized thermal sensory an alyzer (TSA). This was a double-blind, random, comparative, controlled, sin gle-dose and single-center study. Itch was experimentally induced in both f orearms by intracutaneous injection of histamine in 18 subjects. Hydrocorti sone 1%, 2.5% and placebo were applied to test sites on both forearms. The thermal threshold for warmth sensation, cold sensation, cold and heat pain was measured with the TSA. Itch magnitude was measured each minute after hi stamine injection for 10 min with a visual analogue scale (VAS). Itch durat ion was also recorded. In comparison to placebo, 2.5% hydrocortisone signif icantly (p = 0.03) reduced itch duration from 12.6 +/- 11.0 min (mean +/- S D) to 8.6 +/- 8.2 min (the reducing rate was 32%) as well as itch magnitude (at minutes 3, 6, 7 and overall). Placebo, 1% and 2.5% hydrocortisone sign ificantly altered (p <0.05) the cold sensation threshold. No treatment alte red cold or heat pain thresholds. These data suggest that topical applicati on of 2.5% hydrocortisone may be significantly beneficial for the treatment of histamine-induced itch. The correlation between thermal measurements an d antipruritic effects warrants further study. Copyright (C) 2000 S. Karger AG, Basel.