Most of us are not normal...
Recent data suggests that most of us are not normal when it comes to drug metabolism because of our genetics.
In a recent retrospective analysis published in the American Journal of Health-Systems Pharmacy, the authors found that only 7% of over 14,000 patients tested were normal metabolizers for all five of the main drug metabolizing enzyme pathways (i.e., CYP2D6, CYP2C19, CYP2C9, CYP3A4 and CYP3A5). The other 93% of patients had at least one ‘abnormal’ or ‘at-risk’ phenotype.
Pharmacogenetic testing for the CYP450 drug-metabolizing enzymes has been available for decades, albeit grossly underutilized.
Due to the high prevalence of abnormal phenotypes of the five main drug metabolizing enzymes which are responsible for breaking down the majority of medications in the liver, the authors suggest that routine pharmacogenetic testing makes sense in all patients.
Abnormal phenotypes range from Poor Metabolizers to Ultra Rapid Metabolizers. The clinical repercussions of these abnormal phenotypes include potential intolerances, early discontinuations, toxicities and treatment failures. Perhaps more important to note is that patients with these at-risk phenotypes may require dose modifications or use of alternative medications. Fortunately, utilizing pharmacogenetic testing, we have a way to prevent some of these repercussions from occurring.
So we ask, “Are you normal?”