Contact urticaria with systemic symptoms due to hexylene glycol in a topical corticosteroid: case report and review of hypersensitivity to glycols

We report a case of severe contact urticaria with systemic involvement resembling an anaphylactic reaction, following the application of a topical corticosteroid. This was caused by hexylene glycol, an excipient in the formulation. Glycols are widely used in cosmetics, foods and topical and systemic drugs. In particular, glycols are present in many topical drugs used by dermatologists. To our knowledge, this is the first case in the literature of a potentially life-threatening immediate-type reaction in the context of a contact urticaria syndrome due to hexylene glycol. The classification of contact urticaria syndrome and the allergenic potential of glycols are reviewed. Dermatologists should be aware of the contact urticaria syndrome and of the increasing use of glycols in topical drug formulation in order to identify possible adverse reactions.