GeneSight Testing: What It Can and Cannot Tell You

Written By Izabella Alpert

If you have tried a psychiatric medication that did not help, or one that caused side effects that were hard to live with, you may have heard about GeneSight testing. GeneSight is a genetic test that looks at how your body may process and respond to certain mental health medications. This post explains what the test measures, what the research shows, what it costs, and how I use the results in care.

This article is for general education and is not medical advice. Please talk with your prescriber before starting, stopping, or changing any medication.

What GeneSight is

GeneSight Psychotropic is a pharmacogenomic test from Myriad Genetics. Pharmacogenomics is the study of how genes affect the way a person responds to medications. The test uses a cheek swab to look at variations in several genes. Some of these genes, such as CYP2D6 and CYP2C19, guide liver enzymes that break down many antidepressants and other psychiatric medications. Others relate to how certain medications act in the body.

The report sorts more than 60 mental health medications into three groups:

  • Use as directed (green): no gene-drug interaction is expected to change how the medication is used.

  • Moderate gene-drug interaction (yellow): the medication may still be used, sometimes with a dose change or closer monitoring.

  • Significant gene-drug interaction (red): the medication may still be an option, but a different dose or a different first choice is often considered.

A medication in the yellow or red group is not off limits. The groups are a starting point for a conversation, not a list of medications that will or will not work for you.

Potential benefits

  • Information about metabolism. Some people break down certain medications very quickly and may have low blood levels at usual doses. Others break them down slowly and may be more likely to have side effects.

  • Help after medications have not worked. When one or more medications did not help or were hard to tolerate, results can help narrow the next choice.

  • Dosing guidance for some medications. The Clinical Pharmacogenetics Implementation Consortium (CPIC) publishes dosing recommendations for several antidepressants based on CYP2D6 and CYP2C19 results, and the FDA lists known gene and drug associations for a number of psychiatric medications.

  • Results that last. Your genes do not change, so the results can also inform medication choices in the future.

What the research shows

The evidence is mixed, and it is worth describing plainly.

  • The GUIDED trial (2019) studied adults with depression who had not done well on at least one medication. In more than 1,100 participants, test-guided care did not significantly improve average symptom scores at eight weeks, which was the main outcome. It did show higher response rates (26.0% compared with 19.9%) and remission rates (15.3% compared with 10.1%) than usual care.

  • A 2026 randomized trial in JAMA Network Open tested SSRI prescribing guided by CYP2D6 and CYP2C19 results. This trial did not use GeneSight. Symptoms were not different at three months, but remission rates were higher at six months (48.3% compared with 39.4%).

  • A 2024 American Psychiatric Association workgroup review concluded that the current evidence does not support routine use of pharmacogenomic testing for everyone being treated for depression. The FDA has also cautioned against relying on these tests alone to choose an antidepressant.

In plain terms, testing may modestly improve the chance of feeling better for some people, especially after earlier medications have not worked. It is not a guarantee, and most people starting their first medication do not need it.

What the test cannot do

  • It cannot diagnose a mental health condition.

  • It cannot tell you which medication will work best for you.

  • It does not check for allergies or for interactions between medications you already take.

  • It does not replace a clinical evaluation. Your symptoms, history, other health conditions, and preferences still guide treatment.

Medications you take can also change how your body handles other medications. For example, bupropion, fluoxetine, and paroxetine slow down the CYP2D6 enzyme. A person with typical CYP2D6 genes can process some medications like a slow metabolizer while taking them. This is one reason results are always reviewed alongside your full medication list.

Who may want to consider testing

Testing may be worth discussing if:

  • You have tried one or more medications that did not help enough.

  • You had strong side effects at usual or low doses.

  • You and your prescriber are choosing among several reasonable options and want more information.

Testing is usually not needed before a first medication trial, and it should not delay treatment.

How the process works

  • We decide together. We talk at a visit about whether testing makes sense for you.

  • I place the order. GeneSight mails a collection kit to your home.

  • You collect the sample. The cheek swab takes a few minutes, and you send it back in the included packaging.

  • Results arrive. Results usually reach me about three days after the lab receives your sample.

  • We review them at a visit. We go over the report together and decide on next steps. I do not change medications based on the report alone.

What it costs

GeneSight bills you directly. My practice does not charge a separate fee for the test and does not add a markup.

  • You will not pay more than $330 without agreeing to it first. Every patient can choose the $330 self-pay rate, and if your insurance would leave you owing more, GeneSight contacts you before running the test. GeneSight reports that 98% of patients pay $330 or less.

  • With insurance, you may pay nothing. Many plans cover the test. Medicare Part B and most Medicaid plans typically cover it in full, and coverage under commercial plans varies.

  • Your insurance statement may show a much larger amount. The price GeneSight bills to insurance is far higher than $330. That billed amount is not what you owe.

  • Financial help: income-based assistance is available for those who qualify, and interest-free payment plans are offered for balances of $100 or more.

The time we spend deciding on testing and reviewing results is part of a regular visit. For patients in Pennsylvania and New Jersey who use insurance through Headway, visits are billed to insurance. For private pay patients, standard visit fees apply. See Insurance & Fees for details.

The bottom line

GeneSight can add useful information, especially after medication trials that did not go well. It works best as one part of a careful evaluation, not as a shortcut. If you are curious whether testing fits your situation, bring it up at your next visit.

References

Izabella Alpert
Previous

Choosing a Psychiatric Nurse Practitioner for ADHD Care by Telehealth
Next

After a Psilocybin Session: What’s Normal, What Helps, and When to Reach Out