Psoriasis improved by anthracene with near ultraviolet light.

Anthracene with near ultraviolet (UV) light (UVA, 320--400 nm) has been shown previously to inhibit epidermal deoxyribonucleic acid (DNA) synthesis and mitosis. This suggested that the combination of anthracene and UVA light could suppress the rapidly proliferating epidermis of psoriasis. In this preliminary clinical study, anthracene plus UVA light improved psoriasis as shown by thinning of plaques and decreased scale in four of five patients, with complete or almost complete clearing in two of these four patients. These findings indicate that anthracene with UVA light might be helpful in the control of psoriasis.