Pharmacogenetics (PGX) is the study of how people respond differently to drugs based on their inherited genetics. Inherited genetic differences in drug metabolic pathways can affect an individual’s responses to drugs, both in terms of therapeutic effect as well as adverse effects.The activity of drug-metabolizing enzymes often varies widely among healthy people, making metabolism an important variable when deciding to prescribe certain medications. These panels are often used in Cardiology and Psychiatry.

This relatively new field combines pharmacology, the science of drugs, and genomics, the study of genes and their functions, to develop effective, safe medications and doses that will be tailored to a person’s genetic makeup.

Many current drugs are “one size fits all,” but they don’t work the same way for everyone. It can be difficult to predict who will benefit from a medication, who will not respond at all, and who will experience negative side effects (called adverse drug reactions). Adverse drug reactions are a significant cause of hospitalizations and deaths in the United States. With the knowledge gained from the Human Genome Project, researchers are learning how inherited differences in genes affect the body’s response to medications. These genetic differences will be used to predict whether a medication will be effective for a particular person and to help prevent adverse drug reactions.