Editing Drug interaction (section)

==== CYP450 ====
[[Cytochrome P450]] is a very large family of [[hemeprotein|haemoprotein]]s (hemoproteins) that are characterized by their [[enzyme|enzymatic]] activity and their role in the metabolism of a large number of drugs.<ref>{{GoldBookRef|title=cytochrome P450|file=CT06821}} {{cite journal | vauthors = Danielson PB | title = The cytochrome P450 superfamily: biochemistry, evolution and drug metabolism in humans | journal = Current Drug Metabolism | volume = 3 | issue = 6 | pages = 561–97 | date = December 2002 | pmid = 12369887 | doi = 10.2174/1389200023337054 }}</ref> Of the various families that are present in humans, the most interesting in this respect are the 1, 2 and 3, and the most important enzymes are [[CYP1A2]], [[CYP2C9]], [[CYP2C19]], [[CYP2D6]], [[CYP2E1]] and [[CYP3A4]].<ref name="Nelson">Nelson D (2003). [http://drnelson.utmem.edu/P450lect.html Cytochrome P450s in humans] {{webarchive |url=https://web.archive.org/web/20090710050953/http://drnelson.utmem.edu/P450lect.html |date=July 10, 2009 }}. Consulted 9 May 2005.</ref>
The majority of the enzymes are also involved in the metabolism of [[endogenous]] substances, such as [[steroid]]s or [[sex hormones]], which is also important should there be interference with these substances. The function of the enzymes can either be stimulated ([[enzyme induction]]) or inhibited ([[enzyme inhibition]]).