Everyone has unique genes that code for enzymes that are needed to activate or break down a medication. The level of activity of an enzyme (slow, intermediate, fast acting) will determine how the body will react to that medication. There are many people who are on clopidogrel (Plavix), an inactive drug, which requires the enzyme CYP2C19 to activate before it can have its therapeutic effect.

If a patient is a poor metabolizer of CYP2C19, the enzyme is not able to activate clopidogrel; therefore, the concentration of active metabolite is greatly decreased to almost none. This can cause therapeutic failure and put patients at risk for stroke or heart attacks. A pharmacogenomics test before a patient starts clopidogrel could be a life changer for a patient. It can be a life-and-death situation in some cases. So, pharmacogenomics plays a key factor in many disease states.

There are many people who are on omeprazole (Prilosec) for stomach acid, which is a CYP2C19 inhibitor. This is the same enzyme needed for activation of clopidogrel. Taking both would inhibit the activation of clopidogrel, which again means no therapeutic effect. This is a classic example of a drug-gene interaction.

With a painless cheek swab, a pharmacogenomics test can be done to help understand genetic makeup so that medications can be personalized. Learn more