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CYP2C19/clopidogrel Pharmacogenomic Lab Test

  • The CYP2C19 genetic test is used to predict how you will respond to a “blood thinner” medication called clopidogrel (Plavix).

  • Routine CYP2C19testing for clopidogrel is usually not done at this time. Your health care provider will decide if this test is appropriate for you.

  • If your test result shows you have a reduced capacity to process clopidogrel, talk with your health care provider about your options.

  • If your test result shows you process clopidogrel at a normal rate, a standard dose will generally be suggested.

Your health care provider evaluates your test results and uses this information, along with your other health information, to make recommendations for appropriate treatment options.

CYP2C19 Test Results

What should I do with my test results?

Talk to your health care provider or pharmacist about the results. They may suggest that you:

  • Keep taking a medication
  • Change the dose of a medication
  • Stop taking a medication
  • Take a different medication

What does my CYP2C19 test result mean?

Poor Metabolizer

Your body processes (metabolizes) clopidogrel poorly. Talk with your health care provider about other medications that may be a better option for you.

Poor to Intermediate Metabolizer

Your body processes (metabolizes) clopidogrel more slowly and you may not be able to receive the full benefit of this medication. Talk with your health care provider about this or another medication that may be a better option for you.

Intermediate Metabolizer
Extensive Metabolizer

Your body processes (metabolizes) clopidogrel at a normal rate. A standard dose will generally be suggested.

Intermediate to Ultra Rapid Metabolizer
Extensive to Ultra Rapid Metabolizer
Ultra Rapid Metabolizer

Who will see my results?

Only health care professionals, and those individuals to whom you have given permission, may view your genetic test results. If you are receiving care at another medical facility, Mayo Clinic recommends you share this information with your other health care providers.

How could the CYP2C19 test result affect my treatment with clopidogrel?

If you have a CYP2C19 gene variant, your health care provider may suggest you take a different medication.

Who is affected? Do different populations respond differently?

Up to 50% of people have a CYP2C19 gene variant which affects how they process (metabolize) clopidogrel. While these differences are relatively widespread across many populations, individuals of Asian ancestry are the most likely to have the CYP2C19 gene variant.

Other considerations:

Routine CYP2C19 testing for clopidogrel is not recommended at this time.

What is clopidogrel?

Clopidogrel (Plavix) is a medication used to treat or prevent strokes and heart attacks. Clopidogrel works to prevent the blood from clotting so that it flows easily through the body. Clopidogrel is often called a “blood thinner”.

Which gene affects my response to clopidogrel?

Variants in the CYP2C19 gene influence the way your body processes (metabolizes) clopidogrel and can affect your response to this medication.

What problems can patients with the CYP2C19 gene variants have when taking clopidogrel?

Patients who have a CYP2C19 gene variant process (metabolize) clopidogrel more slowly and may not receive the full benefit of this medication. Talk with your health care provider about other medications that may be a better option for you.

Where can I find more information about clopidogrel?

More information about clopidogrel you might find helpful includes:

These resources may help you understand more about individualized medicine, genomics and drug-gene testing (pharmacogenomics):

If you have questions about your test results, ask to speak with your health care provider at your Mayo Clinic care location:

  • Minnesota 507-284-2511

  • Arizona 480-301-8000

  • Florida 904-953-2000