Allergy to Unna boots in four patients.

We report the cases of four patients seen in our department since 1967 with allergic reactions to preservatives in Unna boots. The first three patients had reactions to parabens and the last had a photoallergic reaction to hexachlorophene. Preservative-free Unna boots were successfully applied to patients with allergy to parabens. A table of some currently available Unna boots, detailing their ingredients, is also presented.