Aspirin and Other Anti-Clotting Drugs

Anti-clotting drugs that inhibit or break up blood clots are used at every stage of heart disease. They are generally classified as either anti-platelets or anticoagulants. Both anti-platelets and anticoagulants prevent blood clots from forming but they work in different ways. Anti-platelets prevent blood platelets from sticking together. Anticoagulants are “blood thinners” that stop blood from clotting. Anti-platelets and anticoagulants carry the risk of bleeding, which can lead to dangerous situations, including stroke.

Appropriate anticlotting medications are started immediately in all patients. Such drugs are sometimes used along with thrombolytics, and also as on-going maintenance to prevent a heart attack.

Anti-Platelet Drugs. These drugs inhibit blood platelets from sticking together, and therefore help to prevent clots. Platelets are very small disc-shaped blood cells that are important for blood clotting.

  • Aspirin. Aspirin is an antiplatelet drug. An aspirin should be taken immediately after a heart attack begins. It can be either swallowed or chewed, but chewing provides more rapid benefit. If the patient has not taken an aspirin at home, it will be given at the hospital. It is then continued daily (usually 81 mg/day). Using aspirin for heart attack patients has been shown to reduce mortality. It is the most common anti-clotting drug, and most people with heart disease are advised to take it daily in low dose on an ongoing basis.
  • Clopidogrel (Plavix, generic), a thienopyridine, is another type of anti-platelet drug. Clopidogrel is started either immediately or right after angioplasty/PCI is performed. It is also begun after thrombolytic therapy. Patients who receive a drug-eluting stent should take clopidogrel along with aspirin for at least 1 year to reduce the risk of clots. Some patients may need to take clopidogrel on an ongoing basis. Clopidogrel can increase the risk of upper gastrointestinal (GI) bleeding. Discuss with your doctor whether you should take a proton pump inhibitor (PPI). PPIs can reduce the risk of GI bleeding but they also can interfere with clopidogrel’s anti-clotting effects. .
  • Prasugrel (Effient) is a newer thienopyridine that may be used instead of clopidogrel in patients with acute coronary syndrome (ACS). It should not be used by patients who have a history of stroke or transient ischemic attack.
  • Ticagrelor (Brilinta) is another new antiplatelet approved for patients with ACS. It works differently than thienopyridines.
  • Glycoprotein IIb/IIIa Inhibitors. These powerful anti-platelet drugs include abciximab (ReoPro), eptifibatide (Integrilin), and tirofiban (Aggrastat). They are administered intravenously in the hospital and are used with angioplasty/PCI or coronary artery bypass graft (CABG) surgery.

Anticoagulant Drugs. Anticoagulants thin blood. They include:

  • Heparin is usually begun during or at the end of treatment with thrombolytic drugs and continued for at least 2 days if not the whole time in the hospital.
  • Other intravenous anticoagulants that may be given in the hospital include bivalirudin (Angiomax), fondaparinux (Arixtra), and enoxaparin (Lovenox).
  • Warfarin (Coumadin, generic). Dabigatran (Pradaxa) and rivaroxaban (Xarelto) are other options for patients with atrial fibrillation.

All of these drugs pose a risk for bleeding.