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Nonresponse and resistance to aspirin

James L Zehnder, MD
Udaya S Tantry, PhD
Paul A Gurbel, MD
Section Editors
Lawrence LK Leung, MD
Donald Cutlip, MD
Deputy Editor
Gordon M Saperia, MD, FACC


Aspirin, an acetylated salicylate (acetylsalicylic acid), is classified among the nonsteroidal antiinflammatory drugs. These agents reduce the signs and symptoms of inflammation and exhibit a broad range of pharmacologic activities, including analgesic, antipyretic, and antiplatelet properties. Aspirin is most commonly used for the primary and secondary prevention of cardiovascular disease (CVD) by taking advantage of its antiplatelet properties. (See "Aspirin: Mechanism of action, major toxicities, and use in rheumatic diseases".)

Aspirin, along with P2Y12 platelet inhibitors, statins, and control of modifiable risk factors, is a key component of strategies to improve CVD outcomes in patients with and without CVD. When used for secondary prevention, antiplatelet therapies reduce nonfatal CVD events by approximately one-fourth and fatal events by approximately one-sixth. Given the importance of aspirin in preventive strategies, failure of aspirin to achieve its potential benefit in patients at risk for CVD events is an important clinical issue. This topic will address issues of aspirin nonresponse and resistance and apparent treatment failure for patients taking aspirin [1]. The various uses of aspirin in the treatment of patients with CVD are discussed separately.

(See "Benefits and risks of aspirin in secondary and primary prevention of cardiovascular disease".)

(See "Antithrombotic therapy for elective percutaneous coronary intervention: General use".)

(See "Antiplatelet therapy for secondary prevention of stroke".)


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Literature review current through: Sep 2016. | This topic last updated: Jun 8, 2016.
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