What is Pharmacogenetics?

Pharmacogenetics (PGx) is the study of genetic variations in the human body in relation to a person’s ability to metabolize and process prescription and OTC drugs. While pharmacogenetics gained traction after a 1950s study of the effects of specific medications on different individuals based on their genetic makeup, medical science has known for over 1,500 years that many individuals react differently to certain medications.

Pharmacogenetics: The Basics

Researchers were able to conclude that individuals who have certain genetic variations respond differently to prescribed drugs than those who are without those variations. That is to say that the same dosage, timing and frequency of a drug treatment plan of care may have the ability to metabolize as anticipated in one patient, while it may metabolize differently in another, all based on that individual’s genetic makeup.


The study of pharmacogenetics and the process of pharmacogenetic testing allows healthcare providers the ability to analyze gene markers that can highlight a patient’s inability to process or metabolize a drug as expected. This allows the provider to prescribe a drug treatment plan personalized to a specific patient.

How Pharmacogenetic Testing Works

Pharmacogenetics in practice is built on the foundation of pharmacogenetic testing, which evaluates the basic unit of genetic material, known as a gene, and the segments of DNA that provide instruction for producing specific proteins or enzymes. Each gene within the human body consists of a unique genetic code that is made up of different nucleotides, and individual genetic variations occur throughout the population. While some genetic variations do not produce noticeable negative effects, others are known to cause specific disease or conditions. Similarly, some genetic variations are known to impact an individual’s response to certain drugs.


Pharmacogenetic tests seek out genetic variations within individual patients that are associated with responses to prescription medications, found in genes that are used to produce drug-metabolizing enzymes, medication targets, or the proteins involved in the immune system process. Healthcare providers use pharmacogenetics testing to determine which genetic variations are predominant, and this information is used to understand a patient’s future response to certain medications. Providers can perform pharmacogenetic testing prior to or throughout the duration of a drug treatment plan to help understand an individual’s potential drug response.


The study of pharmacogenetics and the process of pharmacogenetic testing is important to the future of healthcare as more prescription drugs come to market. Individuals who are in need of a drug treatment program for the management or cure of specific diseases can be negatively impacted by the adverse drug reactions that result from less than ideal medication regimens. Pharmacogenetics helps alleviate the need for trial and error in the treatment of patients, and offers a way to strategically target care based on an individual’s genetic code.