C: CYP2C9

Wed, 29 Apr 2026 18:03:39 +0000

# Understanding CYP2C9: A Key Player in Drug Metabolism and Clinical Relevance CYP2C9 is a critical cytochrome P450 enzyme encoded by the CYP2C9 gene, playing a central role in the metabolism of a wide range of commonly prescribed medications. This enzyme is predominantly expressed in the liver and contributes significantly to the breakdown of drugs used for pain management, cardiovascular conditions, diabetes control, and anticoagulation therapy. Understanding CYP2C9 activity is vital for personalized medicine, as genetic variations in this gene can profoundly impact drug efficacy and safety. ## What is CYP2C9? CYP2C9 belongs to the superfamily of cytochrome P450 enzymes, which are essential for oxidizing xenobiotics—including pharmaceuticals—and facilitating their elimination from the body. The enzyme metabolizes approximately 15–20% of clinically used drugs, notably warfarin, fenofibrate, ibuprofen, and tolbutamide. Variations in the CYP2C9 gene leads to altered enzyme activity, resulting in different metabolic profiles: poor, intermediate, extensive, or ultra-rapid metabolizers.