Diagnosis of Aspirin Hypersensitivity in Aspirin Exacerbated Respiratory Disease

Inclusion Criteria: 1. Participants of both sexes aged 18 years and older. 2. Patients with a history of ASA-induced asthma who had at least one asthma attack after ingestion of aspirin or other NSAIDs. 3. Patients with a history of ASA-tolerant asthma who had been occasionally using aspirin or other NSAIDs without any adverse reactions. Exclusion Criteria: 1. Mental or legal incapacitation, or significant emotional problems, or a history of psychiatric disorders at the time of the enrollment. 2. Pregnancy or breastfeeding at the time of enrollment. 3. History of a severe anaphylactic reaction precipitated by ASA and/or other NSAIDs (such as ibuprofen, naproxen, indomethacin, Advil, Aleve, Motrin, diclofenac, etc.). 4. History of a severe bronchospasm precipitated by ASA and/or other NSAIDs requiring an endotracheal intubation. 5. Chronic kidney disease (a calculated GFR based on the Modification of Diet in Renal Disease (MDRD) equation is \< 60 mL/min/1.73 sq.meter). 6. Chronic liver disease by history and/or abnormal liver function tests (SGOT and SGPT ≥ 3 times above upper normal range). 7. Baseline FEV1 \< 70% (or \< 1.5 L) of predicted, or an exacerbation of asthma in the 6 weeks preceding the study. 8. An active infectious disease. 9. Anemia that requires work-up, black stools, active bleeding. 10. A history of gastrointestinal bleeding due to aspirin or other NSAIDS, gastritis, or duodenal ulcer not proven to be due to Helicobacter pylori. 11. A history of hemophilia or any other bleeding disorder. 12. Unstable angina. 13. Participants taking aspirin and or other NSAIDs at the time of the study visits. 14. Participants taking leukotriene receptors inhibitors or 5-lypooxygenase (5-LO) inhibitors at the time of the study visits. 15. In addition, participants taking one or more of the following drugs intake last 14 days prior to the enrollment will be excluded: lithium, warfarine, enoxaparin, heparin, dalteparin, fluconazole, ketotifen. Short-acting antihistamines should be stopped 5 days before the challenge; long-acting antihistamines should be stopped 1 week prior to the challenge.