Studies on the Sensitizing Capacity of Imidazole and Triazole Derivatives. Part II.

Abstract

Eleven azole derivatives (5 imidazoles, 4 benzimidazoles, 2 triazoles) used as antimycotics for topical and systemic treatment in humans and animals have been experimentally investigated by an advanced sensitization method using guinea pigs. Following initial sensitization in a three-step procedure, croconazole (previously called cloconazole) was shown to be a strong sensitizer and bifonazole to be, a moderate sensitizer. The other azole derivatives gave only weak challenge reactions. Fluconazole remained negative. These findings are in agreement with the observation that those azole derivatives used frequently worldwide have been seen extremely rarely as the cause of allergic contact dermatitis. However, the only strong sensitizer among the imidazole derivatives studied so far, croconazole, has caused at least 18 cases of specific hypersensitivity since its introduction to the Japanese and Korean markets. It is highly probable that its sensitizing potential is correlated with the methylene group in the molecule that is lacking in all other azole derivatives.