Allergic contact dermatitis caused by resorcinol and sodium dehydroacetate in a patient with leg ulcers.

Resorcinol, also known as resorcin (1,3-dihydroxybenzene; CAS no. 108-46-3), is an important ingredient of Castellani’s paint solution, an antifungal preparation that is commonly used in daily dermatological clinical practice. Apart from its use in hair dyes, resorcinol is also used in several other topical preparations, because of its antipruritic, keratolytic and antimycotic properties. Sodium dehydroacetate (CAS no. 4418-26-2) is a preservative used in several topical products, in particular for the treatment of ulcers, and has already been reported to be sensitizing (1, 2). We describe a case of allergic contact dermatitis caused by resorcinol and sodium dehydroacetate in a patient affected by leg ulcers.