Editing Medical cannabis (section)

=== Excretion ===
Due to substantial metabolism of THC and CBD, their metabolites are excreted mostly via [[feces]], rather than by urine.<ref name=":0" /><ref name="devinsky">{{cite journal | vauthors = Devinsky O, Cilio MR, Cross H, Fernandez-Ruiz J, French J, Hill C, Katz R, Di Marzo V, Jutras-Aswad D, Notcutt WG, Martinez-Orgado J, Robson PJ, Rohrback BG, Thiele E, Whalley B, Friedman D | title = Cannabidiol: pharmacology and potential therapeutic role in epilepsy and other neuropsychiatric disorders | journal = Epilepsia | volume = 55 | issue = 6 | pages = 791–802 | date = June 2014 | pmid = 24854329 | pmc = 4707667 | doi = 10.1111/epi.12631 }}</ref> After delta-9-THC is hydroxylated into 11-OH-THC via CYP2C9, CYP2C19, and CYP3A4, it undergoes phase II metabolism into more than 30 metabolites, a majority of which are products of [[glucuronidation]]. Approximately 65% of THC is excreted in feces and 25% in the urine, while the remaining 10% is excreted by other means.<ref name=":0" /> The terminal half-life of THC is 25 to 36 hours,<ref>{{cite journal | vauthors = Grotenhermen F | title = Pharmacokinetics and pharmacodynamics of cannabinoids | journal = Clinical Pharmacokinetics | volume = 42 | issue = 4 | pages = 327–60 | date = 2003-04-01 | pmid = 12648025 | doi = 10.2165/00003088-200342040-00003 | s2cid = 25623600 }}</ref> whereas for CBD it is 18 to 32 hours.<ref name=devinsky/>

CBD is hydroxylated by P450 liver enzymes into 7-OH-CBD. Its metabolites are products of primarily CYP2C19 and CYP3A4 activity, with potential activity of CYP1A1, CYP1A2, CYP2C9, and CYP2D6.<ref>{{Cite journal |vauthors=Zendulka O, Dovrtělová G, Nosková K, Turjap M, Šulcová A, Hanuš L, Juřica J |date=2016-02-29|title=Cannabinoids and Cytochrome P450 Interactions|url=http://www.eurekaselect.com/137749/article|journal=Current Drug Metabolism|language=en|volume=17|issue=3|pages=206–226|doi=10.2174/1389200217666151210142051|pmid=26651971|access-date=1 November 2017|archive-date=3 July 2021|archive-url=https://web.archive.org/web/20210703094804/https://www.eurekaselect.com/137749/article|url-status=live}}</ref> Similar to delta-9-THC, a majority of CBD is excreted in feces and some in the urine.<ref name=":0" /> The terminal half-life is approximately 18–32 hours.<ref>{{cite journal | vauthors = Ohlsson A, Lindgren JE, Andersson S, Agurell S, Gillespie H, Hollister LE | title = Single-dose kinetics of deuterium-labelled cannabidiol in man after smoking and intravenous administration | journal = Biomedical & Environmental Mass Spectrometry | volume = 13 | issue = 2 | pages = 77–83 | date = February 1986 | pmid = 2937482 | doi = 10.1002/bms.1200130206 }}</ref>