Medications Affected by Pharmacogenomics

Many commonly prescribed medications are metabolized by enzymes whose activity varies based on your genetics. When a drug relies on a specific enzyme for activation or clearance, genetic variants in the gene encoding that enzyme can change how effectively the drug works — or whether it causes adverse effects.

The Clinical Pharmacogenetics Implementation Consortium (CPIC) publishes evidence-based guidelines for drug-gene pairs where genetic testing can inform prescribing. These guidelines assign evidence levels: Level A (genetic information should be used to change prescribing) and Level B (genetic information could be used to change prescribing). DecodeMyBio reports include only Level A and B interactions.

Each medication page below explains the drug's clinical use, the pharmacogene(s) involved, how metabolizer status can affect the drug, and what CPIC guidelines recommend. These pages provide context for understanding your Medication Safety Report and preparing for conversations with your healthcare provider.

To understand the science behind these interactions, read What Is Pharmacogenomics? or learn about how pharmacogenomic testing works. For details on the data behind every finding, see our methodology.

Medication Pages

Clopidogrel (Plavix)

CPIC Level A

Antiplatelet therapy — CYP2C19 metabolizer status affects activation of this prodrug

Primary gene: CYP2C19

Codeine

CPIC Level A

Opioid prodrug — CYP2D6 metabolizer status determines morphine conversion and safety

Primary gene: CYP2D6

Escitalopram (Lexapro)

CPIC Level A

SSRI antidepressant — CYP2C19 metabolizer status affects drug exposure and side-effect risk

Primary gene: CYP2C19

Sertraline (Zoloft)

CPIC Level A

SSRI antidepressant — CYP2C19 contributes to metabolism; dosing guidance available

Primary gene: CYP2C19

Paroxetine (Paxil)

CPIC Level A

SSRI antidepressant — CYP2D6 metabolizer status affects drug exposure; paroxetine also inhibits CYP2D6

Primary gene: CYP2D6

Atomoxetine (Strattera)

CPIC Level A

Non-stimulant ADHD medication — CYP2D6 poor metabolizers can have up to 10-fold higher drug exposure

Primary gene: CYP2D6

Aripiprazole (Abilify)

CPIC Level A

Atypical antipsychotic — CYP2D6 poor metabolizers have ~80% higher exposure; FDA labeling recommends dose reduction

Primary gene: CYP2D6

Venlafaxine (Effexor)

CPIC Level A

SNRI antidepressant — CYP2D6 affects parent-to-metabolite ratio; both parent drug and metabolite are active

Primary gene: CYP2D6

Amitriptyline (Elavil)

CPIC Level A

Tricyclic antidepressant — CYP2C19 and CYP2D6 together determine metabolism; CPIC recommends dose adjustments for both genes

Primary gene: CYP2C19 + CYP2D6

Simvastatin (Zocor)

CPIC Level A

Statin therapy — SLCO1B1 genotype affects myopathy risk and recommended dose limits

Primary gene: SLCO1B1

Warfarin (Coumadin)

CPIC Level A

Anticoagulant therapy — CYP2C9 and VKORC1 genotypes together guide dosing

Primary gene: CYP2C9 + VKORC1

Check Your Medication Interactions

If you have raw DNA data from 23andMe, AncestryDNA, MyHeritage, or FamilyTreeDNA, you can upload it to DecodeMyBio. Your Medication Safety Report checks over 100 drug-gene interactions across 13 pharmacogenes, identifying any medications where your genetics may warrant a conversation with your prescriber. You can preview a sample report to see the format.

Pharmacogenomic information is one factor among many in medication decisions. Drug response also depends on age, weight, organ function, other medications, and environmental factors. See our Limitations page for a complete discussion. Always consult your healthcare provider before making medication changes.