Editing Oxycodone (section)

== Interactions ==

Oxycodone is [[metabolism|metabolized]] by the [[enzyme]]s [[CYP3A4]] and [[CYP2D6]]. Therefore, its [[clearance (pharmacology)|clearance]] can be altered by [[enzyme inhibitor|inhibitor]]s and [[enzyme inducer|inducer]]s of these enzymes, increasing and decreasing [[half-life]], respectively.<ref name="Forbes2007" /> (For lists of CYP3A4 and CYP2D6 inhibitors and inducers, see [[CYP3A4#Ligands|here]] and [[CYP2D6#Ligands|here]], respectively.) Natural [[genetic variation]] in these enzymes can also influence the clearance of oxycodone, which may be related to the wide inter-individual variability in its half-life and [[potency (pharmacology)|potency]].<ref name="Forbes2007" />

[[Ritonavir]] or [[lopinavir/ritonavir]] greatly increase [[Blood plasma|plasma]] concentrations of oxycodone in healthy human volunteers due to inhibition of CYP3A4 and CYP2D6.<ref name="NieminenHagelberg2010">{{cite journal | vauthors = Nieminen TH, Hagelberg NM, Saari TI, Neuvonen M, Neuvonen PJ, Laine K, Olkkola KT | title = Oxycodone concentrations are greatly increased by the concomitant use of ritonavir or lopinavir/ritonavir | journal = European Journal of Clinical Pharmacology | volume = 66 | issue = 10 | pages = 977–985 | date = October 2010 | pmid = 20697700 | doi = 10.1007/s00228-010-0879-1 | s2cid = 25770818 | url = https://hal.archives-ouvertes.fr/hal-00614173/file/PEER_stage2_10.1007%252Fs00228-010-0879-1.pdf }}</ref> [[Rifampicin]] greatly reduces plasma concentrations of oxycodone due to strong induction of CYP3A4.<ref name="NieminenHagelberg2009">{{cite journal | vauthors = Nieminen TH, Hagelberg NM, Saari TI, Pertovaara A, Neuvonen M, Laine K, Neuvonen PJ, Olkkola KT | title = Rifampin greatly reduces the plasma concentrations of intravenous and oral oxycodone | journal = Anesthesiology | volume = 110 | issue = 6 | pages = 1371–1378 | date = June 2009 | pmid = 19417618 | doi = 10.1097/ALN.0b013e31819faa54 | doi-access = free }}</ref> There is also a case report of [[fosphenytoin]], a CYP3A4 inducer, dramatically reducing the analgesic effects of oxycodone in a chronic pain patient.<ref name="Pon, Hwang, 2015">{{cite journal | vauthors = Pon D, Hwang J, Lo T, Zyl CV | title = Decreased responsiveness to oxycodone: A case of a pharmacokinetic drug interaction? | journal = Journal of Opioid Management | volume = 11 | issue = 4 | pages = 357–361 | year = 2015 | pmid = 26312962 | doi = 10.5055/jom.2015.0284 }}</ref> Dosage or medication adjustments may be necessary in each case.<ref name="NieminenHagelberg2010" /><ref name="NieminenHagelberg2009" /><ref name="Pon, Hwang, 2015" />