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Clopidogrel Bisulfate Oral tablet

It helps to prevent blood clots

Generic Name: clopidogrel  |  Brand Name: Plavix

Brand Names: Plavix

There is an FDA Alert for this drug. Click here to view it.

  • Clopidogrel is a prodrug; requires activation by CYP enzyme system (principally by CYP2C19) to produce its pharmacologically active metabolite.
  • Genetic variations of CYP2C19 can result in impaired metabolism and reduced effectiveness of clopidogrel. (See Reduced Efficacy Associated with Impaired CYP2C19 Function under Cautions.) Higher rates of major adverse cardiovascular events (e.g., death, MI, stroke) have been reported in poor metabolizers of CYP2C19 receiving clopidogrel at recommended dosages following acute coronary syndrome or PCI compared with those who have normal CYP2C19 function.
  • Genetic tests are available to determine a patient's CYP2C19 genotype; results of such tests may be used to guide treatment decisions.
  • Consider use of other antiplatelet agents or alternative dosing strategies for clopidogrel in patients with variant CYP2C19 genotypes.


FDA approved a REMS for clopidogrel to ensure that the benefits of a drug outweigh the risks. However, FDA later rescinded REMS requirements. See the FDA REMS page ([Web]) or the ASHP REMS Resource Center ([Web]).

What is this medicine?

CLOPIDOGREL (kloh PID oh grel) helps to prevent blood clots. This medicine is used to prevent heart attack, stroke, or other vascular events in people who are at high risk.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of the following conditions:
  • bleeding disorder
  • bleeding in the brain
  • planned surgery
  • stomach or intestinal ulcers
  • stroke or transient ischemic attack
  • an unusual or allergic reaction to clopidogrel, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a drink of water. Follow the directions on the prescription label. You may take this medicine with or without food. Take your medicine at regular intervals. Do not take your medicine more often than directed.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

  • aspirin
  • blood thinners like cilostazol, enoxaparin, ticlopidine, and warfarin
  • certain medicines for depression like citalopram, fluoxetine, and fluvoxamine
  • certain medicines for fungal infections like ketoconazole, fluconazole, and voriconazole
  • certain medicines for HIV infection like delavirdine, efavirenz, and etravirine
  • certain medicines for seizures like felbamate, oxcarbazepine, and phenytoin
  • chloramphenicol
  • fluvastatin
  • isoniazid, INH
  • medicines for inflammation like ibuprofen and naproxen
  • modafinil
  • nicardipine
  • over-the counter supplements like echinacea, feverfew, fish oil, garlic, ginger, ginkgo, green tea, horse chestnut
  • quinine
  • stomach acid blockers like cimetidine, omeprazole, and esomeprazole
  • tamoxifen
  • tolbutamide
  • topiramate
  • torsemide

What should I watch for while using this medicine?

Visit your doctor or health care professional for regular check ups. Do not stop taking your medicine unless your doctor tells you to.

If you are going to have surgery or dental work, tell your doctor or health care professional that you are taking this medicine.

Certain genetic factors may reduce the effect of this medicine. Your doctor may use genetic tests to determine treatment.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • black, tarry stools
  • blood in urine or vomit
  • breathing problems
  • changes in vision
  • fever
  • sudden weakness
  • unusual bleeding or bruising

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • constipation or diarrhea
  • headache
  • pain in back or joints
  • stomach upset

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature of 59 to 86 degrees F (15 to 30 degrees C). Throw away any unused medicine after the expiration date.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Last Updated: June 08, 2010
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