Editing Naloxone (section)

==Side effects==

Administration of naloxone to somebody who has used opioids may cause rapid-onset [[opioid withdrawal]].<ref name=britch>{{cite journal |vauthors=Britch SC, Walsh SL |title=Treatment of opioid overdose: current approaches and recent advances |journal=Psychopharmacology (Berl) |volume=239 |issue=7 |pages=2063–2081 |date=July 2022 |pmid=35385972 |pmc=8986509 |doi=10.1007/s00213-022-06125-5 |type=Review}}</ref>

Naloxone has little to no effect if opioids are not present.<ref>{{Cite web |date=2023-08-29 |title=Opioid overdose |url=https://www.who.int/news-room/fact-sheets/detail/opioid-overdose |access-date=2023-11-17 |website=[[World Health Organization]] (WHO) }}</ref> In people with opioids in their system, it may cause increased sweating, nausea, restlessness, trembling, vomiting, flushing, and headache, and has in rare cases been associated with heart rhythm changes, [[seizures]], and [[pulmonary edema]].<ref>{{cite web |url=https://www.drugs.com/sfx/naloxone-side-effects.html |title=Naloxone Side Effects in Detail |website=Drugs.com |access-date=5 May 2015 |url-status=live |archive-url=https://web.archive.org/web/20150507072325/http://www.drugs.com/sfx/naloxone-side-effects.html |archive-date=7 May 2015 }}</ref><ref name="pmid3662194">{{cite journal | vauthors = Schwartz JA, Koenigsberg MD | title = Naloxone-induced pulmonary edema | journal = Annals of Emergency Medicine | volume = 16 | issue = 11 | pages = 1294–1296 | date = November 1987 | pmid = 3662194 | doi = 10.1016/S0196-0644(87)80244-5 }}</ref>

Naloxone has been shown to block the action of pain-lowering [[endorphin]]s the body produces naturally. These endorphins likely operate on the same opioid receptors that naloxone blocks. It is capable of blocking a [[placebo]] pain-lowering response if the placebo is administered together with a hidden or blind injection of naloxone.<ref name="pmid15820838">{{cite journal | vauthors = Sauro MD, Greenberg RP | title = Endogenous opiates and the placebo effect: a meta-analytic review | journal = Journal of Psychosomatic Research | volume = 58 | issue = 2 | pages = 115–120 | date = February 2005 | pmid = 15820838 | doi = 10.1016/j.jpsychores.2004.07.001 }}</ref> Other studies have found that placebo alone can activate the body's μ-opioid endorphin system, delivering pain relief by the same receptor mechanism as morphine.<ref>{{cite news|url=http://sitn.hms.harvard.edu/flash/2016/just-sugar-pill-placebo-effect-real/|title=More Than Just a Sugar Pill: Why the placebo effect is real - Science in the News|date=14 September 2016|work=Science in the News|access-date=14 November 2017|archive-date=15 November 2017|archive-url=https://web.archive.org/web/20171115015402/http://sitn.hms.harvard.edu/flash/2016/just-sugar-pill-placebo-effect-real/|url-status=live}}</ref><ref>{{cite journal | vauthors = Carvalho C, Caetano JM, Cunha L, Rebouta P, Kaptchuk TJ, Kirsch I | title = Open-label placebo treatment in chronic low back pain: a randomized controlled trial | journal = Pain | volume = 157 | issue = 12 | pages = 2766–2772 | date = December 2016 | pmid = 27755279 | pmc = 5113234 | doi = 10.1097/j.pain.0000000000000700 }}</ref>

Naloxone should be used with caution in people with cardiovascular disease as well as those who are currently taking medications that could have adverse effects on the cardiovascular system such as causing [[Hypotension|low blood pressure]], [[pulmonary edema|fluid accumulation in the lungs]] (pulmonary edema), and [[arrhythmia|abnormal heart rhythms]]. There have been reports of abrupt reversals with opioid antagonists leading to pulmonary edema and [[ventricular fibrillation]].<ref name="uptodate_naloxone_contra">{{cite web|url=https://www.uptodate.com/contents/naloxone-drug-information|title=Naloxone: Contraindications|website=[[UpToDate]]|access-date=31 October 2017|url-access=subscription|archive-date=20 May 2016|archive-url=https://web.archive.org/web/20160520232432/http://www.uptodate.com/contents/naloxone-drug-information|url-status=live}}</ref>

Use of naloxone to treat people who have been using opioids recreationally may cause acute [[opioid withdrawal]] with distressing physiological symptoms such as shivering, [[tachycardia]], and nausea; these in turn may lead to aggression and reluctance to receive further treatment.<ref name=ukpg>{{cite web |type=Practice guideline |page=181 |url=https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/673978/clinical_guidelines_2017.pdf |date=November 2017 |publisher=[[Public Health England]] |title=Drug misuse and dependence: UK guidelines on clinical management }}</ref>