Rapid oral challenge-desensitization for patients with aspirin-related urticaria-angioedema

Background: Acetylsalicylic acid (ASA), commonly known as aspirin, is indicated in the treatment of coronary artery disease (CAD). Many patients are denied treatment with ASA because of a history of ASA or nonsteroidal anti-inflammatory drug (NSAID)-induced urticaria or angioedema. Objective: We sought to develop a safe and practical protocol to allow the administration of ASA to patients with a history of ASA- or NSAID-induced urticaria-angioedema. Methods: Eleven subjects with a history of ASA- or NSAID-induced urticaria-angioedema were challenged-desensitized by oral protocols based on rapidly escalating doses of ASA. Most had CAD, one had a history of pulmonary embolism, and one had refractory chronic sinusitis and asthma. Starting doses ranged from 0.1 to 10 mg and were administered at intervals of 10 to 30 minutes. Dosing was individualized for each patient but followed this general sequence (in milligrams): 0.1, 0.3, 1, 3, 10, 20,40, 81, 162, 325. Results: Nine patients tolerated the procedure without adverse effects and continued taking ASA for periods ranging from 1 to 24 months, without development of urticaria or angioedema. A patient who had a history of chronic idiopathic urticaria in addition to aspirin-induced urticaria had chest tightness during the protocol. Another patient who had continuing urticaria and angioedema associated with antithyroid antibodies developed angioedema several hours after completing the protocol. Conclusion: In patients with historical ASA- or NSAID-induced urticaria-angioedema reactions but who did not have urticaria and angioedema independent of ASA/NSAID, rapid oral challenge-desensitization to ASA was performed safely and permitted patients with CAD and other diseases to receive treatment with ASA.