CYTOCHROME-P450 - NEW NOMENCLATURE AND CLINICAL IMPLICATIONS

Many drug interactions are a result of inhibition or induction of cyto chrome P450 enzymes (CYP450). The CYP3A subfamily is involved in many clinically significant drug interactions, including chose involving no nsedating antihistamines and cisapride, that may result in cardiac dys rhythmias. CYP3A4 and CYP1A2 enzymes are involved of many psychotherap eutic agents. The protease inhibitors, which are used to treat patient s infected with the human immunodeficiency virus, are metabolized by t he CYP450 enzymes and consequently interact with a multitude of other medications. By understanding the unique functions and characteristics of these enzymes, physicians may better anticipate and manage drug in teractions and may predict or explain nit individual's response to a P articular therapeutic regimen.