[Are the NSAIDs able to compromising the cardio-preventive efficacy of aspirin?]

Some studies have recently suggested a potential pharmacodynamic interaction between aspirin and some non-selective non-steroidal anti-inflammatory drugs (NSAIDs). We have evaluated the reality of this pharmacodynamic interaction and analyse its clinical pertinence.

Literature review (Medline search - December 2005).

Several ex vivo studies show that some non-selective NSAIDs can block the active site of Cox1 thus preventing aspirin from exerting its platelet anti-aggregating cardio-preventive action. Cox2 selective molecules do not act at this site. The few studies, mainly case reports, have analysed the potential loss of the cardiovascular preventive benefit of aspirin in patients receiving concomitantly non-selective anti-inflammatory drugs with controversial results.

It seems necessary to know the existence of this pharmacodynamic interaction between aspirin at a low dose and some non-selective anti-inflammatory drugs notably ibuprofen and naproxen. In the absence of a clear clinical demonstration, it is advisable to avoid the non-selective NSAIDs in patients treated with a low dose of aspirin. It might be advisable to switch to an anti-aggregating treatment other than aspirin (clopidrogel, etc.) in these cases. At the present time, however, there are no data on which to base such a recommendation.