Hypersensitivity to ketoconazole.

We report a patient who experienced generalized urticaria and facial angioedema following oral administration of ketoconazole. Skin prick tests with ketoconazole and oral challenge were positive. Conjugates of ketoconazole with human serum albumin were used for the in vitro study, obtaining a positive result in the histamine release test. No significant levels of IgE antibodies to ketoconazole were found by RAST. Controls did not react to any of these tests. These results suggest that the patient developed a type I hypersensitivity reaction to ketoconazole. In this case, skin prick tests with ketoconazole and histamine release test with a conjugate of ketoconazole with human serum albumin were useful in ketoconazole hypersensitivity diagnosis. Finally, skin tests with other imidazole agents were carried out, including metronidazole, ornidazole, and fluconazole that were negative.