Clopidogrel is used alone or together with aspirin to lessen the chance of a heart attack or stroke. It is given to patients who have already had a heart attack, severe chest pain, or a stroke, or to patients with other circulation problems that could cause a stroke or heart attack.
A heart attack or stroke may occur when a blood vessel is blocked by a blood clot. Clopidogrel is a platelet inhibitor. It reduces the chance that a harmful blood clot will form by preventing platelets from clumping together in the blood. Clopidogrel may also increase the chance of serious bleeding in some people.