Ibuprofen antiplatelet effect

Low-dose aspirin is associated with a reduced risk of major bleeding, particularly GI bleeding. Other GI disturbances (e.g., dyspepsia, nausea) are infrequent with low-dose aspirin. Ibuprofen should not be administered on a regular basis concurrently with aspirin because it may block aspirin s antiplatelet effects. 

Because of reported antiplatelet effects, patients using anticlotting medications (eg, warfarin, aspirin, ibuprofen) should use garlic cautiously. Additional monitoring of blood pressure and signs and symptoms of bleeding is warranted. Garlic may reduce the bioavailability of saquinavir, an antiviral protease inhibitor, but it does not appear to affect the bioavailability of ritonavir. 

ASPIRIN ANALGESICS - NSAIDs 1. Risk of gastrointestinal bleeding when aspirin, even a low dose, is co-administered with NSAIDs 2. Ibuprofen 1 antiplatelet effect of aspirin 1. Additive effect 2. Ibuprofen competitively inhibits binding of aspirin to platelets 1. Avoid co-administration 2. Avoid co-administration... 

Low doses (<100 mg) of aspirin quickly inhibit cyclooxygenase in all the platelets in the circulation. Therefore, the onset of the antiplatelet effect of aspirin is less than 60 minutes. It has been reported, however, that some patients either have or develop aspirin resistance and may require higher doses to achieve the desired antiplatelet effect. Despite this, routine testing for aspirin resistance is not recommended. It was observed recently that administration of ibuprofen prior to the administration of a daily aspirin dose prohibits the aspirin from binding irreversibly to the cyclooxygenase and may decrease its antiplatelet effect. Current recommendations are to administer aspirin at least 2 hours before ibuprofen or to wait at least 4 hours after an ibuprofen dose. 

A number of pharmacodynamic studies have investigated whether or not NSAIDs affect the antiplatelet effects of aspirin. Celecoxib 200 mg twice daily, diclofenac 75 mg twice dailyetoricoxib 120 mg daily, lumira-coxib 400 mg daily, meloxicam 15 mg dailynaproxen 500 mg twice daily, parecoxib 40 mg twice dailyand rofecoxib 25 mg daily have all been shown not to alter the antiplatelet effects of aspirin in doses of 75 to 325 mg daily. The effects of ibuprofen ate less elear, and may be related to the order of drug administration. 

The evidence currently available on the antagonism of antiplatelet effects is insufficient to recommend that ibuprofen is not used with low-dose aspirin. Nevertheless, some have concluded that when patients taking low-dose aspirin for cardioprotection require long-term NSAIDs for inflammatory conditions, the use of diclofenac or naproxen would seem preferable to ibuprofen.A coxib was also suggested as an alternative,but the subsequent suggestion of an increased risk of serious cardiovascular effects with the coxibs (as a class ) probably precludes this. Recently the Commission on Human Medicines (CHM) in the UK has advised that there may be a small increased risk of thrombotic events with the non-selective NSAIDs, particularly when used at high doses and for long-term treatment. ... 

Paracetamol levels are increased by diflunisal. Aspirin, diclofenac, nabumetone and sulindac pharmacokinetics do not appear to be affected by paracetamol. There is no pharmacokinetic interaction between ibuprofen and paracetamol. Propacetamol, and possibly paracetamol, increase the antiplatelet effects of diclofenac, although the evidence is limited and the clinical relevance of this is uncertain. 

Preparations from plant materials containing salicylate have been used to treat pain and fever (Stone, 1763) from ancient times into the nineteenth century, when synthetic salicylic acid was synthesized in Germany and used for the same purposes. Acetyl salicylate, aspirin, synthesized as a prodrug for salicylate, was introduced by Bayer in 1899 (Dreser, 1899) and is still widely used to treat pain, fever, and inflammation. In low doses aspirin is also used by many to reduce the incidence of heart attacks by an antithrombotic effect (Antiplatelet Trialists Collaboration, 1994). Eventually, other drugs with therapeutic effects similar to those of aspirin were introduced, including indomethacin, ibuprofen, and naproxen. These... 

Reversible inhibitors of COX 1 and COX 2, with analgesic, antipyretic, and anti-inflammatory actions, include ibuprofen, naproxen, indomethacin, ketorolac, and sulindac. When used as antiinflammatory agents, they are usually no more effective than ASA, but they may be better tolerated. All have antiplatelet actions (reversible) at moderate (not low) doses and cause bleeding tendencies. 

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