Pharmacogenetic or pharmacogenomic (PGx) testing analyzes your DNA to help predict how you may respond to certain medications. By identifying genetic variations that affect drug metabolism and drug action, PGx testing supports more personalized prescribing, helping clinicians choose medications and doses that are more likely to work well while reducing the risk of side effects. Testing is typically done using a simple cheek swab, saliva sample, or sometimes blood; results can inform care for conditions such as mental health disorders, chronic pain, and cardiovascular disease. PGx testing is generally available with a written physician order.
What PGx testing can show
It can classify how you metabolize medications, such as fast, normal, or slow metabolizer status; these differences can affect outcomes:
Toxicity: drug levels may build up and increase adverse drug reactions.
Hypersensitivity: normal drug levels may still trigger severe reactions in susceptible individuals.
Lack of efficacy: the body may not achieve therapeutic levels, reducing benefit.
What PGx testing does in practice
Identifies drug-gene interactions that influence how drugs are absorbed, broken down, or responded to.
Predicts likelihood of effectiveness for selected medications.
Estimates risk for serious side effects or adverse reactions.
Supports dosing decisions to avoid under-dosing or over-dosing.
Why genes matter
Genes provide instructions for making enzymes and other proteins that help process medications. Genetic differences can change how much enzyme is produced or how well it functions. If a medication is metabolized too quickly, too slowly, or not effectively, typical doses may lead to poor response or increased side effects.
When PGx testing is commonly used
History of significant side effects.
Multiple past medication trials with limited benefit.
Starting medications where genetics are known to influence response, such as certain antidepressants, blood thinners, and pain relievers.
Proactive planning to avoid preventable medication problems in chronic conditions like depression, anxiety, hypertension, and pain.
How the process works
Sample collection via cheek swab or saliva.
Laboratory analysis of relevant genes.
A report is sent to your clinician.
Your healthcare provider combines results with your medical history and other factors to guide medication selection and dosing.
Key benefits
More personalized treatment choices.
Faster path to an effective regimen.
Safer prescribing and fewer preventable adverse reactions.
Results remain relevant for life and can be kept in your medical record for future prescribing decisions.
