Pharmacogenetic Testing (PGx)
No two people are the same. From how we look, down to our smallest genetic code, we are all unique. So why are we prescribed medication based on how well it works for someone else?
Thanks to a new scientific field called “pharmacogenetics,’ we now understand that variations in each person’s DNA determine how well a particular medication will work in their body. Pharmacogenetic testing (PGx) discovers these genetic variants and can tell your physician what the most effective medication and dosage is for your specific body based on your unique DNA.
How DNA affects medication
Drug Receptors
Some medications work by attaching to receptors located on the surface of the cell. The shape, number, and function of these receptors are defined by your DNA. If someone has a different type of receptor or no receptor at all, the medication may be ineffective.
Drug Uptake
Other medications work by absorbing into the cell itself, called “uptake.” A person’s unique DNA determines the rate at which the cell will absorb the medication. If absorption is lower than the drug manufacturer intended, the medication may not work properly. It is also possible that their DNA expells the medication at a faster rate than intended, altering its effectiveness.
Drug Breakdown
A person’s DNA also determines the speed at which the body breaks down a medication. Someone who metabolizes the drug faster may need a higher dosage to achieve the intended therapeutic result, while someone who breaks down the medication slower may need a smaller dose.
Risks of Adverse Drug Reactions
A key benefit of Pharmacogenetic Testing (PGx) is reducing the risk of Adverse Drug Reactions (ADRs). Despite rigorous testing by the U.S. Food and Drug Administration (FDA), there is still a risk that a medication can cause unintended side effects, often related to your unique DNA dictating how your body processes a medication. The FDA describes ADRs as “unwanted undesirable effects” that can “vary from minor problems like a runny nose to life-threatening events, such as a heart attack or liver damage.”1
The overall risks of ADRs are significant, leading to an estimated 100,000+ deaths each year.2 Studies show that 98% of people carry at least one genetic variant known to cause atypical drug results.3
Pharmacogenetic Testing (PGx) can identify these genetic variants so you and your physician can make the most educated and precise treatment plan and reduce the chances of a serious adverse drug reaction.
PGx Testing Process
Oral swab
PGx testing uses a simple mouth swab of your inner cheek. The DNA in your saliva is all that is needed to successfully run the test.
Sample delivered to lab
Your sample is shipped overnight to the Promus testing lab where our professional lab technicians process the sample.
Get results
A PGx report is delivered electronically within 48 hours that includes a comprehensive list of significant genetic variants.
Medication types affected by DNA variation
There are many classes of medications that have known pharmacogenetic associations, meaning the drug may cause an atypical reaction in some patients or could result in an adverse drug reaction in some cases. The FDA monitors these known associations and provides a database of medications and their corresponding pharmacogenetic risks. Links to these databases are provided as well as a list of drug classes with known associations.
Cardiovascular
Statins, Blood Thinners (Anticoagulants), Beta Blockers, Antiplatelets, ACE Inhibitors, Vasodilators, Platelet Stimulators, Antidiuretics
Psychiatry
SSRIs, Benzodiazepines, Antipsychotics, Tricyclic Antidepressants
Gastroenterology
Proton Pump Inhibitors, 5-ASA Derivatives
Endocrinology
Sulfonylureas, Antihyperlipidemics, Thyroid Drugs
Urology & Gynecology
Urinary Antispasmodics, Alpha-blockers, Estrogens, Progestins
Immunology
Immunosuppresants, Calcineurin Inhibitors
Infectious Disease
Antibiotics, Antivirals, Antifungals, Antimalarials
Neurology
Anticonvulsants, Cholinergic muscle stimulants, Multiple Sclerosis Drugs, VMAT2 inhibitors, Antiemetics
Oncology
5-HT3 Antagonists, Antineoplastic Agents, Estrogen Modulators, Purine Analogs, Pyrimidine Analogs
Pain Management
NSAIDs, Opioids
- https://www.fda.gov/drugs/information-consumers-and-patients-drugs/finding-and-learning-about-side-effects-adverse-reactions
- https://www.fda.gov/drugs/drug-interactions-labeling/preventable-adverse-drug-reactions-focus-drug-interactions
- Rollinson V, Turner R, Pirmohamed M. Pharmacogenomics for Primary Care: An Overview. Genes (Basel). 2020 Nov 12;11(11):1337. doi: 10.3390/genes11111337. PMID: 33198260; PMCID: PMC7696803.
