Clopidogrel is used to prevent heart attacks and strokes in persons with heart disease (recent heart attack), recent stroke, or blood circulation disease (peripheral vascular disease). It is also used with aspirin to treat new/worsening chest pain (new heart attack, unstable angina) and to keep blood vessels open and prevent blood clots after certain procedures (such as cardiac stent). Clopidogrel works by blocking platelets from sticking together and prevents them from forming harmful clots. It is an antiplatelet drug. It helps keep blood flowing smoothly in your body.