Onychodystrophy After Topically Applied Fluorouracil for Warts

To the Editor.— The only things harder to cure than warts are periungual warts. Fluorouracil has been mentioned in both the scientific and the "underground" literature as a treatment for viral warts, periungual,¹sub-ungual,²verrucae planae,³and "viral warts."⁴Onychodystrophy due to fluorouracil in the treatment of periungual warts was reported several years ago.⁵Since this medication is now eminently available for topical use, it is time to report this problem again. Report of a Case.— A 15-year-old boy was seen on April 21, 1970, with several large, steadfast, periungual warts which had been present for about three years. He was advised to apply fluorouracil cream to each wart at bedtime, and then to cover the warts with adhesive tape overnight. He called five weeks later to report that the warts were smaller, but the tips on his fingers (not the warts) were tender. Treatment