Platelet Inhibition by Aspirin, Acetaminophen and NSAID

Nonsteroidal antiinflammatory drugs such as diclofenac or naproxen may interfere with the inhibition of platelet aggregation by aspirin, because they all interact with the platelet cyclooxygenase.This may be of great clinical importance because of an increased cardiovascular event rate (myocardial infarction, stroke). The present randomized, controlled study analyses in vitro platelet aggregation under a combined treatment of healthy volunteers with aspirin and either acetaminophen, diclofenac, naproxen, or placebo.

An in vivo study on healthy volunteers with combinations of well established drugs

Inclusion Criteria:

• Healthy volunteers

Exclusion Criteria:

• Administration of drugs affecting platelets
• History of bleeding
• Gastrointestinal disorders
• Hypersensitivity to aspirin and/or NSAID
• Pregnancy and breast feeding