1 alpha,25-(OH)2D3 use on psoriasis and ichthyosis.

The present work compared the clinical efficacy of topically applied 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25-(OH)2D3) in 16 cases with psoriasis vulgaris, 5 with ichthyosis vulgaris and 8 with X-linked ichthyosis. Sixty-nine percent of the psoriatic cases responded to 1 alpha,25-(OH)2D3 therapy, whereas no ichthyotic patients responded. The present study confirms the previously suggested effectiveness of the active form of vitamin D3 for psoriasis and denies its possible efficiency against the ichthyoses. Direct suppression of hyperproliferative activity of the psoriatic epidermis is considered one of the most plausible mechanisms of 1 alpha,25-(OH)2D3 efficacy, through examination of the aforementioned evidence.