Topical 6-aminonicotinamide plus oral niacinamide therapy for psoriasis.

Ninety-nine patients with psoriasis were treated topically with 6-aminonicotinamide (6-AN) in four years. In a double-blind study, 1% 6-AN gel was superior to 0.1% triamcinolone acetonide in 29 comparisons, equal in three, and inferior in one when applied without occlusion for four weeks. In an open study, 1% 6-AN was better than four "potent" steroid creams in 34 comparisons, equal in four, and inferior in one. Substantial improvement or complete clearing of plaques occurred in 85 of 99 patients. Tachyphylaxis occurred in ten, but was not permanent. Mucocutaneous toxicity appeared in 25% but was usually easily controlled. Tinnitus occurred in four, but none had deterioration of audiogram readings. The combination of topical 6-AN and oral niacinamide therapy gives promise of an effective and safe treatment for psoriasis. One of three patients with pityriasis rubra pilaris improved considerably with 6-AN.