HomeLab TestsPharmacogenetic Tests
Back to Lab Tests
Pharmacogenetic Tests
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Lab Tests

Pharmacogenetic Tests

Pharmacogenetic testing examines how your unique genetic makeup influences your body's response to specific medications, helping providers choose the most effective treatments.

What is pharmacogenetic testing?

Pharmacogenetics (also called pharmacogenomics) is the study of how your genes affect the way your body responds to certain medicines. Genes are parts of DNA in your cells that you inherit from your parents. Some genes affect how your body uses and breaks down medicines.

Certain changes (or variants) in these genes may make it harder for your body to absorb a medicine or dosage, meaning the medicine may not work as expected. These genetic differences can explain why some people benefit from a medicine while others do not, or why some people experience serious side effects.

Pharmacogenetic testing looks for these gene changes in a sample of your blood, saliva, or cells swabbed from your cheek.

What is it used for?

Providers use pharmacogenetic testing as part of precision medicine to consider factors like your medical history, lifestyle, and other medications. The test helps providers:

  • Find out whether a certain medicine could be effective for you.
  • Find out how much of the medicine you need.
  • Predict whether you will have a serious side effect from a medicine.

Why do I need pharmacogenetic testing?

Providers most often rely on this testing when considering treatments for:

  • High cholesterol: Variants of the SLCO1B1 gene may increase the risk of muscle pain and weakness when taking certain statins.
  • Depression: Variants of the CYP2D6 or CYP2C19 genes may make it harder to break down some antidepressants.
  • Blood clot prevention: Certain variants may indicate a need for lower doses of the anticoagulant warfarin.
  • HIV: Variations of the HLA-B gene can indicate a risk for severe skin reactions to Abacavir, while CYP2B6 variants can affect the nervous system when taking efavirenz.
  • Multiple sclerosis: Variants of the TPMT or NUDT15 genes may lead to suppressed immune system responses when taking azathioprine.

Testing is also used for specific cancers, such as breast cancer (HER2 protein status), colon cancer (UGT1A1 gene variants), and acute lymphoblastic leukemia (TPMT gene variants).

What happens during the test?

  • Blood test: A professional takes a sample from a vein in your arm using a small needle.
  • Saliva test: You spit into a small tube or use a special swab or pad.
  • Cheek swab: A professional rubs the inside of your cheek with a special swab.

At-home test kits are available, but they should generally not be used for making treatment decisions as they may not be accurate.

What do the results mean?

Your results will describe any changes in the gene tested. These changes can show how certain medicines are likely to affect you, but they cannot diagnose any health conditions or tell you about your risk for developing them. Your provider will use these results alongside other information to recommend or adjust your treatment.

Frequently Asked Questions

No, you generally do not need to fast or make any special dietary changes before this test. Because the test analyzes your DNA, which remains constant throughout your life, food or drink intake does not affect the results. The sample is typically collected via a simple cheek swab, saliva tube, or blood draw, so the process is quick and non-invasive. Will my insurance cover the cost of pharmacogenetic testing?::Coverage varies significantly by insurance provider and the specific clinical context. Many insurers cover these tests when they are ordered for specific conditions with strong evidence, such as determining the correct dose of warfarin for blood clots or selecting antidepressants for treatment-resistant depression. However, for other medications or general wellness purposes, the test may be considered experimental or elective, leaving the patient responsible for the cost. Always verify with your insurance provider and ask your doctor for a pre-authorization if necessary. How long does it take to receive results, and how are they interpreted?::Results typically take one to two weeks to process in a specialized laboratory. The report will not simply say "positive" or "negative" but will categorize your genetic variants into groups such as "normal metabolizer," "poor metabolizer," or "ultra-rapid metabolizer." Your healthcare provider will then use this data to adjust your medication choice or dosage. For example, if you are a poor metabolizer of a specific antidepressant, your doctor might prescribe a different drug or a lower dose to avoid side effects. Does a pharmacogenetic test replace the need for regular blood work or monitoring?::No, pharmacogenetic testing provides a one-time snapshot of your genetic predisposition but does not replace ongoing clinical monitoring. Your body's response to medication can still be influenced by age, liver or kidney function, other medications, and lifestyle factors. You will still need regular blood tests and check-ups to ensure the medication is working effectively and to monitor for any side effects that may arise despite genetic guidance.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

kontakt@hittavard.se

Ⓒ 2024. Alla rättigheter förbehålls av juxt ab

Sök
Om ossVillkor och policyVanliga frågorKontakta oss