Editing Alkaloid (section)

== Applications ==

===In medicine===
Medical use of alkaloid-containing plants has a long history, and, thus, when the first alkaloids were isolated in the 19th century, they immediately found application in clinical practice.<ref>[[#Hesse|Hesse]], p. 303</ref> Many alkaloids are still used in medicine, usually in the form of salts widely used including the following:<ref name="Meyers"/><ref>[[#Hesse|Hesse]], pp. 303–309</ref>

{| Class = "wikitable"
|-
! Alkaloid
! Action
|-
| [[Ajmaline]]
| [[Antiarrhythmic agent|Antiarrhythmic]]

|-
| [[Emetine]]
| [[Antiprotozoal agent]], [[emesis]]
|-
| [[Ergoline|Ergot alkaloids]]
| [[Vasoconstriction]], [[Psychedelic drug|hallucinogenic]], [[Uterotonic]]
|-
| [[Glaucine]]
| [[Antitussive]]
|-
| [[Morphine]]
| [[Analgesic]]
|-
| [[Nicotine]]
| [[Stimulant]], [[Nicotinic agonist|nicotinic acetylcholine receptor agonist]]
|-
| [[Physostigmine]]
| Inhibitor of [[acetylcholinesterase]]
|-
| [[Quinidine]]
| Antiarrhythmic
|-
| [[Quinine]]
| [[Antipyretic]], [[Antimalarial medication|antimalarial]]
|-
| [[Reserpine]]
| [[Antihypertensive drug|Antihypertensive]]
|-
| [[Tubocurarine]]
| Muscle relaxant
|-
| [[Vinblastine]], [[vincristine]]
| [[Chemotherapy|Antitumor]]
|-
| [[Vincamine]]
| [[Vasodilation|Vasodilating]], [[Antihypertensive drug|antihypertensive]]
|-
| [[Yohimbine]]
| [[Stimulant]], [[aphrodisiac]]
|-
|[[Berberine]]
|[[Antihyperglycaemic]]<ref name=":0" />
|}

Many synthetic and semisynthetic drugs are structural modifications of the alkaloids, which were designed to enhance or change the primary effect of the drug and reduce unwanted side-effects.<ref>[[#Hesse|Hesse]], p. 309</ref> For example, [[naloxone]], an [[opioid receptor]] [[receptor antagonist|antagonist]], is a derivative of [[thebaine]] that is present in [[opium]].<ref>[[#Dewick|Dewick]], p. 335</ref>

<gallery class="center skin-invert-image" widths="200px" perrow="2">
File:Thebaine skeletal.svg|[[Thebaine]]
File:Naloxone.svg|[[Naloxone]]
</gallery>

=== In agriculture ===
Prior to the development of a wide range of relatively low-toxic synthetic [[pesticide]]s, some alkaloids, such as salts of nicotine and [[anabasine]], were used as [[insecticide]]s. Their use was limited by their high toxicity to humans.<ref>{{Cite book |last1=Matolcsy |first1=G. |url=https://books.google.com/books?id=fPiRSsUOpLEC&pg=PA21 |title=Pesticide Chemistry |last2=Nádasy |first2=M. |last3=Andriska |first3=V. |date=1989-01-01 |publisher=Elsevier |isbn=978-0-08-087491-3 |pages=21–22 |language=en}}</ref>

=== Use as psychoactive drugs ===
Preparations of plants and fungi containing alkaloids and their extracts, and later pure alkaloids, have long been used as [[Psychoactive drug|psychoactive substances]]. [[Cocaine]], [[caffeine]], and [[cathinone]] are [[stimulant]]s of the [[central nervous system]].<ref>[[#Veselovskaya|Veselovskaya]], p. 75</ref><ref>[[#Hesse|Hesse]], p. 79</ref> [[Mescaline]] and many indole alkaloids (such as [[psilocybin]], [[dimethyltryptamine]] and [[ibogaine]]) have [[hallucinogen]]ic effect.<ref>[[#Veselovskaya|Veselovskaya]], p. 136</ref><ref>{{cite book|title=Ibogaine: Proceedings from the First International Conference (The Alkaloids Book 56)|year=1950|publisher=Elsevier Science |isbn=978-0-12-469556-6|at=p. 8}}</ref> [[Morphine]] and [[codeine]] are strong narcotic pain killers.<ref>[[#Veselovskaya|Veselovskaya]], p. 6</ref>

There are alkaloids that do not have strong psychoactive effect themselves, but are [[precursor (chemistry)|precursor]]s for semi-synthetic psychoactive drugs. For example, [[ephedrine]] and [[pseudoephedrine]] are used to produce [[methcathinone]] and [[methamphetamine]].<ref>[[#Veselovskaya|Veselovskaya]], pp. 51–52</ref> [[Thebaine]] is used in the synthesis of many painkillers such as [[oxycodone]].