In the present study, 40 subjects w

In the present study, 40 subjects were included in the
trial, who were irradiated with the 1.5-fold MED on test
areas on the back. This localization is the best test site of
the body with the smallest fluctuations of the photometric
measurements and the best match of the erythema of
the light scale compared to that of the test sites [19] . The
effect of A. vera gel (97.5%) was compared to DermallergRatiopharm
cream 1% (1% hydrocortisone) and Dermatop
cream (0.25% prednicarbate) as well as 1% hydrocortisone
in placebo gel as positive controls. As expected, the
commercially available potent corticosteroid preparations
resulted in significant erythema suppression already
after 24 h. Also, the well-known blanching effect of
corticosteroids related to vasoconstriction of the superficial
vasculature could be observed in nonirradiated test
areas. A. vera gel (97.5%) also caused a significant inhibition
of UVB-induced erythema but only 48 h after the
first application.