Topical Use of Fluorouracil in the Treatment of Psoriasis

To the Editor.—  The dermatologist's dilemma when treating a benign dermatosis such as psoriasis with systemic methotrexate has certainly raised the need for an effective topical cytostatic. The results with methotrexate itself locally applied were disappointing and so was the first assay with weak fluorouracil.¹ With higher concentration and occlusive dressing, however, fluorouracil was demonstrated to erode and clear psoriatic plaques.² Now Tsuji and Sugai³ report their favorable results in 13 cases of apparently discoid psoriasis. Luger⁴ has earlier presented clinical and histological evidence of the anti-psoriatic effect of the 5% fluorouracil ointment even without occlusion. With the same type of open treatment with 5% fluorouracil ointment Finzi⁵ also noted an anti-psoriatic effect which was more intense and rapid if the lesions were treated with occlusive dressings. We would like to add some data from our own double-blind study.The study was conducted with 12