A double-blind, placebo-controlled study of a commercial Aloe vera gel in the treatment of slight to moderate psoriasis vulgaris.

Paper Abstract

The Aloe vera plant has been used for an array of ailments, including skin diseases. Recent experimental research have substantiated the presence of biologically active compounds in the gel, but there are few controlled, clinical trials to assess the efficacy.

To test the effect of a commercial, preserved, but otherwise untreated Aloe vera gel in psoriasis.

Forty-one patients with stable plaque psoriasis were included in a randomized, double-blind, placebo-controlled right/left comparison. The study comprised a 2-week wash-out period followed by a 4-week treatment period with two daily applications and follow-up visits after 1 and 2 months.

Data on 40 patients were analysed. The score sum of erythema, infiltration and desquamation decreased in 72.5% of the Aloe vera-treated sites compared with 82.5% of the placebo-treated areas from week 0 to week 4, which was statistically significant in favour of the placebo treatment (P = 0.0197). Fifty-five per cent of the patients reported local side-effects, mainly drying up of the skin on test areas.

The effect of this commercial Aloe vera gel on stable plaque psoriasis was modest and not better than placebo. However, the high response rate of placebo indicated a possible effect of this in its own right, which would make the Aloe vera gel treatment appear less effective.