The right drug at the right dose at the right time

CYP2C19/Citalopram Pharmacogenomic Lab Test

Key Facts

This section provides information only about this specific pharmacogenomic test.


  • If you have medication questions, ask your health care provider.
  • Follow your health care provider's instructions when taking any medication.
  • Do not change your medications without talking with your health care provider.
  • CYP2C19 testing is used to determine potential risk for side effects to antidepressant medication like citalopram (Celexa®)
  • Routine CYP2C19 testing for citalopram (Celexa®) is usually not done at this time. Your health care provider will decide if this test is appropriate for you
  • 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
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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 result mean?

Poor or poor to intermediate

Use an alternative due to increased risk of drug side effects

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 Citalopram?

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

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What is Citalopram?

Citalopram (Celexa®) is an antidepressant. Citalopram is used in individuals suffering from depression.

Which gene affects my response to Citalopram?

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

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

Patients who have a CYP2C19 gene variant process (metabolize) citalopram differently than patients without the gene variant. Talk with your health care provider about other medications that may be a better option for you.

Poor and poor to intermediate metabolism of this drug by CYP2C19 has been associated with the potential for increased risk of drug side effects.

Where can I find more information about Citalopram?

More information about citalopram you might find helpful includes:

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

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

  • Minnesota
  • Arizona
  • Florida
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