Allergic Contact Dermatitis

Allergic contact dermatitis (ACD) is a T cell-mediated delayed hypersensitivity reaction (Gell and Coombs Type IV) caused primarily by fragrances and preservatives; and less commonly by emulsifiers found in hand-hygiene products.34,35 ACD is characterized by a rash, redness, and itching, which usually begins 24 to 48 hours after contact with offending allergen and may progress to oozing skin blisters and spread to areas of skin untouched by the product.

ACD has been reported with chlorhexidine, phenolic derivatives, iodine and iodophors, triclosan, and quaternary ammonium compounds. ACD to alcohol-based handrub or to the various additives present in certain formulations is rare.36,37 While ACD with alcohol-based products is uncommon, such reactions may represent true allergy to alcohol, allergy to an impurity or aldehyde metabolites, or allergy to another constituent of the product.30,36