ABSTRACT
Clioquinol is a broad-spectrum antibacterial agent with antifungal properties. It is used as a topical antibacterial and antifungal treatment. However, topical absorption of this iodine-containing agent is rapid and extensive, especially when the skin is covered with an occlusive dressing or if the medication is applied to extensive or eroded areas of the skin, which may affect thyroid function tests. Estimates of the 10-year prevalence of contact allergy to clioquinol in the general population of Denmark based on the CE-DUR method ranged from 0.13% to 0.18%. Contact allergy to clioquinol has also caused an erythema multiforme-like allergic contact dermatitis. Oral administration of clioquinol in patients previously sensitized by topical application of this drug will induce an eruption in some patients: systemic contact dermatitis. Absorption of clioquinol through the skin and mucosae may also have induced systemic contact dermatitis. The clinical picture was classic for systemic contact dermatitis, though, and clioquinol was a very likely candidate.
