Editing Drug interaction (section)

== With herbal medicines ==
Herb-drug interactions are drug interactions that occur between [[herbal medicines]] and conventional drugs.<ref name="bjcp2">{{cite journal|last1=Fugh-Berman|first1=Adriane|last2=Ernst|first2=E.|date=20 December 2001|title=Herb-drug interactions: Review and assessment of report reliability|journal=British Journal of Clinical Pharmacology|volume=52|issue=5|pages=587–595|doi=10.1046/j.0306-5251.2001.01469.x|pmc=2014604|pmid=11736868}}</ref> These types of interactions may be more common than drug-drug interactions because herbal medicines often contain multiple pharmacologically active ingredients, while conventional drugs typically contain only one.<ref name="bjcp2" /> Some such interactions are [[clinically significant]],<ref name="drugs2">{{cite journal|last1=Hu|first1=Z|last2=Yang|first2=X|last3=Ho|first3=PC|last4=Chan|first4=SY|last5=Heng|first5=PW|last6=Chan|first6=E|last7=Duan|first7=W|last8=Koh|first8=HL|last9=Zhou|first9=S|date=2005|title=Herb-drug interactions: a literature review.|journal=Drugs|volume=65|issue=9|pages=1239–82|doi=10.2165/00003495-200565090-00005|pmid=15916450|s2cid=46963549}}</ref> although most herbal remedies are not associated with drug interactions causing serious consequences.<ref>{{cite journal|last1=Posadzki|first1=Paul|last2=Watson|first2=Leala|last3=Ernst|first3=Edzard|date=May 2012|title=Herb-drug interactions: an overview of systematic reviews|journal=British Journal of Clinical Pharmacology|volume=75|issue=3|pages=603–618|doi=10.1111/j.1365-2125.2012.04350.x|pmc=3575928|pmid=22670731}}</ref> Most catalogued herb-drug interactions are moderate in severity.<ref name="ijcp2">{{cite journal|last1=Tsai|first1=HH|last2=Lin|first2=HW|last3=Simon Pickard|first3=A|last4=Tsai|first4=HY|last5=Mahady|first5=GB|date=November 2012|title=Evaluation of documented drug interactions and contraindications associated with herbs and dietary supplements: a systematic literature review.|journal=International Journal of Clinical Practice|volume=66|issue=11|pages=1056–78|doi=10.1111/j.1742-1241.2012.03008.x|pmid=23067030|s2cid=11837548|doi-access=free}}</ref> The most commonly implicated conventional drugs in herb-drug interactions are [[warfarin]], [[insulin]], [[aspirin]], [[digoxin]], and [[ticlopidine]], due to their narrow [[Therapeutic index|therapeutic indices]].<ref name="ijcp2" /><ref>{{cite journal|last1=Na|first1=Dong Hee|last2=Ji|first2=Hye Young|last3=Park|first3=Eun Ji|last4=Kim|first4=Myung Sun|last5=Liu|first5=Kwang-Hyeon|last6=Lee|first6=Hye Suk|date=3 December 2011|title=Evaluation of metabolism-mediated herb-drug interactions|journal=Archives of Pharmacal Research|volume=34|issue=11|pages=1829–1842|doi=10.1007/s12272-011-1105-0|pmid=22139684|s2cid=38820964}}</ref> The most commonly implicated herbs involved in such interactions are those containing [[St. John’s Wort]], magnesium, calcium, iron, or [[ginkgo]].<ref name="ijcp2" />

=== Examples ===
Examples of herb-drug interactions include, but are not limited to:

* St. John's wort affects the clearance of numerous drugs, including [[cyclosporin]], [[SSRI]] antidepressants, [[digoxin]], [[indinavir]], and [[phenprocoumon]].<ref name="bjcp2" /> It may also interact with the anti-cancer drugs [[irinotecan]] and [[imatinib]].<ref name="oncologist2">{{cite journal|last1=Meijerman|first1=I.|last2=Beijnen|first2=J. H.|last3=Schellens|first3=J. H.M.|date=1 July 2006|title=Herb-Drug Interactions in Oncology: Focus on Mechanisms of Induction|journal=The Oncologist|volume=11|issue=7|pages=742–752|doi=10.1634/theoncologist.11-7-742|pmid=16880233}}</ref>
* [[Salvia miltiorrhiza]] may enhance anticoagulation and bleeding among people taking warfarin.<ref name="drugs2" />
* [[Allium sativum]] has been found to decrease the plasma concentration of [[saquinavir]], and may cause [[hypoglycemia]] when taken with [[chlorpropamide]].<ref name="drugs2" />
* [[Ginkgo biloba]] can cause bleeding when combined with warfarin or [[aspirin]].<ref name="drugs2" />
* Concomitant [[Ephedra (medicine)|Ephedra]] and [[caffeine]] use has been reported to, in rare cases, cause fatalities.<ref>{{cite journal|last1=Ulbricht|first1=C.|last2=Chao|first2=W.|last3=Costa|first3=D.|last4=Rusie-Seamon|first4=E.|last5=Weissner|first5=W.|last6=Woods|first6=J.|date=1 December 2008|title=Clinical Evidence of Herb-Drug Interactions: A Systematic Review by the Natural Standard Research Collaboration|journal=Current Drug Metabolism|volume=9|issue=10|pages=1063–1120|doi=10.2174/138920008786927785|pmid=19075623}}</ref>

=== Mechanisms ===
The mechanisms underlying most herb-drug interactions are not fully understood.<ref>{{cite journal|last1=Chen|first1=XW|last2=Sneed|first2=KB|last3=Pan|first3=SY|last4=Cao|first4=C|last5=Kanwar|first5=JR|last6=Chew|first6=H|last7=Zhou|first7=SF|date=1 June 2012|title=Herb-drug interactions and mechanistic and clinical considerations.|journal=Current Drug Metabolism|volume=13|issue=5|pages=640–51|doi=10.2174/1389200211209050640|pmid=22292789}}</ref> Interactions between herbal medicines and anticancer drugs typically involve enzymes that metabolize [[cytochrome P450]].<ref name="oncologist2" /> For example, St. John's Wort has been shown to induce [[CYP3A4]] and [[P-glycoprotein]] in vitro and in vivo.<ref name="oncologist2" />