Kinetics of UV-erythema in normal subjects

In the expanding field of clinical dermatopharmacology we standardized an erythema model for testing drugs with effects on UV-induced inflammation in normal male Caucasian subjects. Using a light source with fibre-optic transmission and precise radiation characteristics, some of the shortcomings of conventional UV-application could be overcome. The radiation geometry during the various experiments was kept constant by a tube, permitting a defined area of exposure. Up to eight skin areas of the backs of normal volunteers were radiated with 86.2% UV-A and 13.8% UV-B. After exclusion of hyporeactive and hyperreactive subjects a good intrasubject reproducibility was obtained repeatedly over at least 3 months. According to the definition of bioavailability, our method allows the measurement of the rate and extent of UV-induced erythema. This model has been used for testing topical steroids, non-steroidal antiphlogistics in a variety of pharmaceutical formulations.