Have you ever taken a medication that didn’t seem to work for you, even though other people say they got great results? Or maybe you’ve taken a common drug and noticed some weird side effects.
Your genes can play a role in how your body reacts to medication. An area of medicine called pharmacogenomics is studying this connection and helping health care providers understand why treatments don’t always work the same for everyone. The goal is to help people find the medication that works best for them.
What is pharmacogenomics?
“Pharmacogenomics, commonly abbreviated ‘PGx,’ is the study of how our genes can affect the way our body handles medicine. It looks at some of the reasons why some drugs work well for certain people but not for others and why some people get more side effects. It can help physicians figure out the right medication or dose for you,” said Esteban Astiazaran Symonds, MD, a geneticist with Banner - University Medicine.
Pharmacogenomics combines pharmacology (how drugs work) and genomics (your genetic information). It is part of a broader area of health care known as personalized medicine, which aims to provide individualized care that’s best for each person.
Health care providers have long known that the same drug can affect people differently. Pharmacogenomics helps explain why and offers ways to choose the right medication and dose based on how a person is likely to respond.
Why your genes matter when it comes to medication
“Some people have genetic variants that make them process medications either too slowly, so drugs build up in the body and increase the risk of side effects, or too quickly, so drugs leave the body too fast which decreases their good effects,” Dr. Symonds said.
There are also people with genetic differences that affect the way medications act.
Medications commonly affected by your genes
Research has found several types of medications that are more likely to be influenced by genetic differences. These include:
- Mental health medications, including antidepressants like escitalopram (Lexapro) and sertraline (Zoloft), as well as antipsychotics
- Pain medications, especially opioids
- Heart medications, including blood thinners like warfarin (Coumadin) and clopidogrel (Plavix) and cholesterol medications like statins
- Cancer therapies, including chemotherapy drugs and targeted therapies
- Anti-seizure medications
- Diabetes medications
- Antibiotics
- Drugs used for organ transplants and immune conditions
If you’ve had trouble with any of these in the past, you may want to talk to your provider about your medication history.
Could pharmacogenomic testing help you?
Pharmacogenomic testing is usually done using a cheek swab or blood test. You may want to consider testing if you:
- Have had side effects from medications that work well for other people
- Have tried different medications without success
- Are about to start a new medication that’s known for gene-drug interactions
- Have a condition where you need long-term or high-risk drug treatment
“PGx testing can be done for a specific gene-drug interaction or as a panel that includes a large number of drug groups,” Dr. Symonds said.
PGx tests don’t look for genetic diseases. They look for common variants in drug-related genes. “Most people will have results indicating a ‘potential’ drug-gene interaction,” Dr. Symonds said. “But most of the results will be for drugs they have never taken and might never take.”
Most experts recommend testing only if a specific pharmacogenomic change might be impacting a drug you have taken or you will need to take. Test results can then help your provider choose the safest and most effective medications for you.
What pharmacogenomics can and can’t tell you
“PGx testing is most helpful when it’s performed by a treating physician or health care provider who knows their patient’s specific health situation,” Dr. Symonds said. “I’d encourage anyone considering pharmacogenomic testing to first consult with their physician or provider to better understand if and how PGx testing could be helpful and what type of PGx testing is the right one for you. By doing this, you can make sure the results will be helpful in improving your health goals.”
While pharmacogenomics is a promising tool, it’s not the only factor in how medications work. “Other factors like interactions between the medications we take, health conditions, age, sex, gut microbiome and our immune system play a major role, too,” Dr. Symonds said.
And not every drug has a known genetic connection. Research is ongoing, and access to testing may depend on your doctor, your health system or your insurance plan.
What to do if you’re curious about pharmacogenomic testing
If you’ve struggled with medications in the past or are starting a new one, talk to your health care provider. They can help you:
- Review your medication list
- Identify if any of your prescriptions are affected by genetic factors
- Decide whether pharmacogenomic testing might be useful
While not every medication requires a genetic test, understanding your options can help you feel more confident in your care. Whether you choose PGx testing or not, you and your provider can work together to find the safest, most effective treatment plan.
How Banner Health can help
Need help managing medications or side effects? At Banner Health, our providers stay informed about new tools like pharmacogenomic testing. We can help you understand your results and create a medication plan that works with your body.
Schedule an appointment online with a Banner Health provider to talk about your concerns and learn about treatment options that may work for you.
