The Asthma Center

Aspirin hypersensitivity

Aspirin hypersensitivity or intolerance is a unique condition that affects a small percentage of the population. If you are sensitive to aspirin, you may develop hives, asthmatic reactions, sinus symptoms, nasal polyp growth and/or anaphylaxis. Recent studies have shown that you may respond to aspirin desensitization. Aspirin desensitization is a method of lowering your sensitivity to aspirin.

Desensitization is carried out by initially administering aspirin in very small doses and gradually increasing the dose every few hours. As doses are gradually increased, tolerance to aspirin is developed. The accumulated small doses of aspirin administered over a few days will often permit safe daily dosing of aspirin. This procedure can usually be carried out over a 1 - 3 day period on an outpatient basis. Typically you should notice symptom improvement – especially in sense of smell – within 1 month of starting daily aspirin. Long term aspirin desensitization may also cause a decreased recurrence rate of nasal polyps. Therefore you may have a decreased need for repeat sinus surgery or oral corticosteroids. Nasal congestion may also improve. Aspirin desensitization is best carried out soon after sinus surgery and polypectomy.

Aspirin desensitization involves the risk of anaphylaxis and needs to be carried out by an experienced allergist in an appropriate setting. Up to 20% of individuals with nasal polyps will spontaneously convert from being aspirin tolerant to intolerant. Therefore aspirin therapy may be considered if you have nasal polyps even without a history of aspirin reactions. This therapy may prevent recurrence of polyps and the development of aspirin intolerance.