clopidogrel (Plavix) vs. heparin (Hemochron)

• Clopidogrel and heparin are blood thinners used to prevent blood clots.
• A brand name for clopidogrel is Plavix.
• Brand names for heparin include Hemochron, Hep-Lock, Hep-Lock U/P, Heparin in 5% Dextrose, Heparin Lock Flush, and HepFlush-10.
• Side effects of clopidogrel and heparin that are similar include bleeding and allergic reactions.
• Side effects of clopidogrel that are different from heparin include diarrhea, rash, itching, abdominal pain, headache, chest pain, muscle aches, dizziness, pancreatitis, and liver failure.
• Side effects of heparin that are different from clopidogrel include low blood platelets (thrombocytopenia), heparin induced thrombocytopenia (HIT), heparin induced thrombocytopenia and thrombosis (HITT), injection site discomfort/irritation, and increased liver enzymes.

Clopidogrel is a type of blood thinner called an anti-platelet drug used for preventing heart attacks, strokes, and death in patients who have had a previous stroke, unstable angina, heart attack, or have peripheral arterial disease (PAD). It prevents blood clots by binding to the P2Y12 receptor on platelets, preventing adenosine diphosphate (ADP) from activating platelets. Clopidogrel is a P2Y12 inhibitor, the same class of drugs that also includes prasugrel (Effient) and ticagrelor (Brilinta). Clopidogrel is similar to ticlopidine (Ticlid) in chemical structure and in the way it works.

Heparin is a widely used injectable anticoagulant used to stop blood clots. The blood coagulation system is composed of various steps and heparin acts at multiple sites in this process. Heparin prevents blood clots by blocking the action of two of the 12 clot-promoting proteins in blood (factors X and II) whose action is necessary for blood to clot.

Clopidogrel

The tolerability of clopidogrel is similar to that of aspirin. The more common side effects of clopidogrel are:

• diarrhea,
• rash,
• itching,
• Abdominal pain
• headache,
• chest pain,
• muscle aches,
• dizziness.
• 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.

Heparin

The most common side effects are hemorrhage (bleeding), thrombocytopenia (decrease platelet count), heparin induced thrombocytopenia (HIT), heparin induced thrombocytopenia and thrombosis (HITT), injection site discomfort/irritation, allergy or hypersensitivity type reactions, and increase in liver enzymes.

Clopidogrel

Clopidogrel bisulfate usually is taken once daily. It can be taken with or without food. Clopidogrel is activated by enzymes in the liver to its active form. Individuals who have reduced activity of liver enzymes that activate clopidogrel due to liver disease may not adequately respond to clopidogrel. Alternative treatments should be used for these patients. The recommended dose for treating unstable angina or heart attack is 300 mg initially followed by 75 mg daily in combination with 75-325 mg of aspirin. Peripheral arterial disease or recent stroke is treated with 75 mg daily.

Heparin

Doses vary considerably based on use and desired level of anticoagulation. Consult published guidelines for various uses (myocardial infarction, DVT, pulmonary embolism, for example) and the manufacturer's recommendations as dosage varies; some patients may require dosage adjustments if they have certain conditions (for example, renal or liver problems).

Clopidogrel

The combination of clopidogrel with nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Motrin, Advil, Nuprin), naproxen (Naprosyn, Aleve), diclofenac (Voltaren), etodolac (Lodine), nabumetone (Relafen), fenoprofen (Nalfon), flurbiprofen (Ansaid), indomethacin (Indocin), ketoprofen (Orudis; Oruvail), oxaprozin (Daypro), piroxicam (Feldene), sulindac (Clinoril), tolmetin (Tolectin), and mefenamic acid (Ponstel) may increase the risk of stomach and intestinal bleeding.

Combining clopidogrel with warfarin (Coumadin) or other drugs that cause bleeding increases the risk of bleeding.

Clopidogrel is converted to its active form by enzymes in the liver. Drugs that reduce the activity of these enzymes, for example, omeprazole (Prilosec, Zegerid) or esomeprazole (Nexium) may reduce the activity of clopidogrel and should not be used with clopidogrel. Other drugs that also may react with clopidogrel in a similar fashion include fluoxetine (Prozac, Sarafem), cimetidine (Tagamet), fluconazole (Diflucan), ketoconazole (Nizoral, Extina, Xolegel, Kuric), voriconazole (Vfend), ethaverine (Ethatab, Ethavex), felbamate (Felbatol), and fluvoxamine (Luvox).

Heparin

Medications that increase the risk of bleeding will add to the effects of heparin and further increase the risk of bleeding that is associated with heparin. Such medications include aspirin, clopidogrel (Plavix), warfarin (Coumadin), other anticoagulants, and nonsteroidal anti-inflammatory drugs such as ibuprofen (Motrin; Advil), naproxen (Naprosyn), diclofenac (Voltaren), and others.

Clopidogrel

There are no adequate studies of clopidogrel in pregnant women.

Studies in rats have shown that clopidogrel appears in breast milk; however, it is not known whether it also appears in human breast milk. Because of a potential for side effects in the nursing infant, the physician must weigh the potential benefits and possible risks before prescribing clopidogrel to nursing mothers.

Heparin

Heparin has not been adequately evaluated in pregnant women. Heparin should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus. Preservative-free heparin is recommended when heparin is needed during pregnancy.

It is not known whether heparin is excreted into breast milk. However, due to its large molecular weight, it is thought that heparin is not likely to be excreted into breast milk. Preservative-free heparin is recommended when heparin is needed during breastfeeding.