The cytochrome P450 gene products are responsible for metabolizing a large number of widely prescribed drugs. Clopidogrel (Plavix®) is metabolized by CYP2C19 to its active form. Individuals with poor-metabolizers of CYP2C19 will require alternative drug therapy due to inability to activate Clopidogrel (Plavix®), while those with ultra-extensive metabolizer phenotype will require a decreased dosage due to higher than normal rates of drug metabolism.