Objective: The study was divided into two parts. The objective of the preliminary study was to evaluate the optimum dose and tolerance of 5-aminolaevulinic acid (5-ALA) compared to a placebo cream with a 633-nm LED light in normal, healthy, volunteer forearm skin. The second study was to establish if ALA-PDT treatments improve the signs of ageing.
Results: Threshold photosensitization was observed using 5% 5-ALA under plastic occlusion for 30 minutes following a dose response study of forearm skin. Mild improvement was observed, using this concentration and time, for periorbital skin aging. Other anecdotal positive results of photo-rejuvenation are reported for facial and chest areas.