Celecoxib, Ibuprofen and the Antiplatelet Effect of Aspirin

Inclusion Criteria: 1. male or female, age 18-75; 2. subjects with osteoarthritis and documented stable ischemic heart disease; 3. the patient is on long-term aspirin prophylaxis for the ischemic condition; 4. the patient requires or is eligible for chronic treatment with an antiinflammatory and/or analgesic drugs given to control osteoarthritis symptoms; 5. female subjects of childbearing potential must have a negative pregnancy test, use adequate contraception during the study and not be lactating; 6. written informed consent before undergoing any study procedure. Exclusion Criteria: 1. active gastrointestinal disease (e.g. Crohn's disease or ulcerative colitis) or any evidence of concomitant disease which may lead to early termination of the study; 2. history of active peptic ulceration, gastrointestinal bleeding, esophageal, gastric or duodenal ulcer; 3. known hypersensitivity to COX-2 inhibitors, analgesics, antipyretics, sulfonamides or NSAIDs; 4. treatment with any investigational drug within the previous 30 days; 5. previous participation in this study; 6. evidence of neoplasm or any other severe disease of any organ, including any psychiatric illness; 7. clinically relevant deviations from the normal range in laboratory tests; 8. recent history or suspicion of alcohol abuse or drug addiction; 9. subjects unlikely to be collaborative or to give reliable answers; 10. pregnancy or lactation; female or childbearing potential without a clinical accepted contraceptive method; 11. any severe pathology that can interfere with the treatment or the clinical or instrumental tests of the trial; 12. intake of antiaggregant, anticoagulant, diuretic, beta-blocker, ACE- inhibitor, lithium, methotrexate, cimetidine, digoxin; 13. contraindications to NSAIDs.