The tolerability of clopidogrel is similar to that of aspirin. Diarrhea, rash, or itching occurs in approximately 1 in 20 persons taking clopidogrel. Abdominal pain also occurs in about 1 in 20 persons, but it is less frequent than with aspirin. Headache, chest pain, muscle aches, and dizziness may also occur. Clopidogrel may also cause severe bleeding, allergic reactions, pancreatitis, and liver failure. Ticlopidine (Ticlid) is an antiplatelet medication quite similar to clopidogrel. It has been associated with a severe reduction in white blood cell count in between 0.8% and 1% of persons. The risk of this dangerous side effect with clopidogrel is about 0.04%, much less than with ticlopidine but twice that of aspirin. Clopidogrel rarely causes a condition called thrombotic thrombocytopenic purpura (TTP) in one out of every 250,000 people. TTP is a serious condition in which blood clots form throughout the body. Blood platelets, which participate in clotting, are consumed, and the result can be bleeding because enough platelets are no longer left to allow blood to clot normally. For comparison, the related drug, ticlodipine (Ticlid), causes TTP 17-50 times more frequently than clopidogrel.
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). It works by blocking certain blood cells called platelets and prevents them from forming harmful blood clots. This “anti-platelet” effect helps keep blood flowing smoothly in your body.