Examples

How It Works

Aspirin is an antiplatelet medicine that decreases blood clot formation by preventing the smallest blood cells (platelets) from sticking together and forming blood clots.

Why It Is Used

Aspirin is the most commonly used medicine to prevent stroke. Aspirin:

• Reduces the risk of stroke in people who have already had a transient ischemic attack (TIA) or ischemic stroke.¹
• Can reduce the risk of stroke in those with an irregular heart rhythm (atrial fibrillation) who cannot take warfarin, an anticoagulant.¹

Aspirin or other antiplatelet drugs may decrease the risk of stroke in people who cannot have surgery to reopen a blocked carotid artery (carotid endarterectomy).

How Well It Works

Aspirin reduces the risk of stroke and heart attack or another transient ischemic attack (TIA) in people who have had a prior stroke or TIA. For every 1,000 people who had a prior stroke or TIA and were treated with aspirin for 3 years, the treatment prevented 25 nonfatal strokes, 6 nonfatal heart attacks, and 15 deaths.¹

When given within 48 hours of an ischemic stroke that has been confirmed by a computed tomography (CT) scan to rule out hemorrhagic stroke, aspirin reduces the risk of death and dependence due to disability and increases the chance of recovery.²

Side Effects

Side effects of aspirin include:

• Skin bruising, especially in older people.
• Irritation of the stomach lining.
• Bleeding from the digestive system.
• Allergic reaction.
• Bleeding (hemorrhage) in the brain (rare) or other internal organs of the body.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

A recent large study showed that aspirin in doses of 75 to 150 mg daily is as effective as higher doses for long-term treatment.³

Aspirin can be started immediately during an ischemic stroke.³

Aspirin may not always be helpful for people older than 75 or younger than 60 who do not have any risk factors for heart disease.

Safety tips when taking aspirin

Follow these safety tips when taking aspirin.

• Take the medicine at the same time each day.
• Take aspirin with food to prevent irritation of the stomach.
• Use buffered or enteric-coated aspirin.
• Check with your doctor before using other nonprescription drugs that contain aspirin, such as Pepto-Bismol.
• Be on the alert for signs of bleeding, and call your doctor immediately if any signs occur.
• Let your doctor know if you are taking aspirin and are planning to have surgery. You may have to stop the aspirin temporarily.

Other medicines are available for people who cannot take aspirin or for whom aspirin is not effective. Clopidogrel (Plavix) is used for people who cannot take aspirin or along with aspirin therapy. Aggrenox is a medicine that combines aspirin and extended-release dipyridamole in one medicine.

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