Allergic contact dermatitis to chloroxylenol.

Chloroxylenol, also known as p-chloro-m-xylenol (PCMX), is a compound that has been used as a preservative in cosmetics and as an active agent in antimicrobial soaps. We present two patients with allergic contact dermatitis from PCMX, confirmed by positive (+++) patch-test reactions at 48 and 72 hours, identification of PCMX in a soap and in a hand cream used by the patients, and improvement following withdrawal of the incriminating products. The mechanism of action, structure, antimicrobial activity, and dangers of PCMX are reviewed.