Clopidogrel is an antiplatelet medication that is used to prevent serious or life-threatening problems with the heart and blood vessels in people who have had a stroke, heart attack, or severe chest pain. It is also used to prevent blood clots after certain procedures, such as cardiac stent, and to keep blood vessels open. Clopidogrel works by preventing platelets from sticking together and forming harmful clots. It is available only with a doctors prescription and comes with a Medication Guide that should be read and understood carefully. Clopidogrel may increase the risk of serious bleeding during surgery, medical procedures, or dental work, and it is important to inform all medical professionals that you are taking this medication.