Urticaria during triple therapy for Helicobacter pylori infection. Clinical implications

Triple therapy, which includes a proton pump inhibitor and two antibiotics, is currently being used in the eradication of Helicobacter pylori. We report a patient who developed malaise and urticaria while she was being treated with omeprazole, amoxicillin, and tinidazole. On withdrawal of the three drugs, the clinical symptoms promptly resolved. Tests for allergy demonstrated that the adverse effects were related to the three drugs and that both cellular and humoral mechanisms were involved. It is stressed that the precise identification of the offending drug(s) and assessment of the mechanisms involved are of importance in the management of patients who remain infected by Helicobacter pylori. This is especially true when considering patients with omeprazole sensitization.