Polyhexamethylene biguanide is a relevant sensitizer in wet wipes

Polyhexamethylene biguanide (PHMB; CAS no. 2875743-3) is a preservative used as a biocide in industrial products (e.g. swimming pool disinfectants), medical devices (e.g. wound cleansers), contact lens solutions, and cosmetics such as wet wipes, deodorants, and facial cleansers. It is considered to be a rare contact allergen, with a sensitization rate of ∼ 0.5% in an unselected population (1, 2). Moreover, sensitization does not seem to be associated with cosmetic exposure (2). Here, we report a case of allergic contact dermatitis following the use of wet wipes containing PHMB.