CYP2C9
Cytochrome P450 2C9
What it does
Co-metabolizes warfarin, NSAIDs, several oral hypoglycemics.
Why this matters for Black patients
African-ancestry populations carry the *5, *6, *8, and *11 variants (reduced activity) at higher frequencies. Standard warfarin dosing calculators that ignore CYP2C9 variants overdose Black patients.
Common variants
| Variant | Phenotype | African | European |
|---|---|---|---|
| *11 | Decreased function | 0.022 | 0.003 |
| *5 | Decreased function | 0.011 | 0.000 |
| *6 | Loss of function | 0.014 | 0.000 |
| *8 | Decreased function | 0.072 | 0.000 |
Note: This page is reference information, not medical advice. Pharmacogenomic differences are about ancestry, not race; race is an imperfect proxy. Discuss any medication changes with your prescriber.