--- description: Ketamine, which has shown promise as a drug that works against depression, may act like an opioid and raise the risk of addiction. title: Ketamine May Ease Depression By Acting Like an Opioid, Study Suggests image: https://static.time.com/v3/assets/bltea6093859af6183b/blt22016aed2cf92797/698938f9457a525deed5f3cb/ketamine.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  * [Health](/section/health/) ## Health Update your preferences in [Account Settings](/account/preferences/) Close * [Drugs](/tag/drugs/) ## Drugs Update your preferences in [Account Settings](/account/preferences/) Close # Ketamine May Ease Depression By Acting Like an Opioid, Study Suggests ## Video: Michael Pollan on the Healing Power of Psychedelics [Watch (HLS stream): Michael Pollan on the Healing Power of Psychedelics](https://cdn.jwplayer.com/manifests/Z7yskoOT.m3u8) (4:20)  _Published 2018-05-16. Author Michael Pollan explored the therapeutic properties of psychedelics for his latest book, "How to Change Your Mind." His research includes firsthand experiences with the drugs._  by [Jamie Ducharme](/author/jamie-ducharme/)  ## Jamie Ducharme Update your preferences in [Account Settings](/account/preferences/) Close Ducharme is a contributor to TIME. Aug 29, 2018 2:47 PM CUT  A patient has Ketamine administered by way of an IV bag for the treatment of depression at IV Solution in Chicago, Wednesday, March 21, 2018. A patient has Ketamine administered by way of an IV bag for the treatment of depression at IV Solution in Chicago, Wednesday, March 21, 2018.Chicago Tribune—TNS via Getty Images  by [Jamie Ducharme](/author/jamie-ducharme/)  ## Jamie Ducharme Update your preferences in [Account Settings](/account/preferences/) Close Ducharme is a contributor to TIME. Aug 29, 2018 2:47 PM CUT [Ketamine](http://time.com/4876098/new-hope-for-depression/ "undefined"), once known primarily as a club drug, has in recent years gained legitimacy among some scientific experts as potential therapy for [hard-to-treat depression](http://time.com/4826620/ketamine-depression-antidepressant/ "undefined"). It works faster than antidepressants but wears off fairly quickly, and the health consequences of taking ketamine over months and years is so far unknown. The drug is FDA-approved as an anesthetic, and several academic centers across the U.S. run ketamine clinics; private ketamine clinics run by doctors have also sprung up. But new research points to what could be a major [drawback of the drug](http://time.com/4696418/the-club-drug-ketamine-may-treat-depression-but-the-risks-could-be-big/ "undefined"). It seems to behave like an opioid in the brain, which experts worry could set patients up for dependence. The small study, published Wednesday in the [_American Journal of Psychiatry_](https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.2018.18020138 "undefined"), suggests that ketamine may work as an antidepressant by activating the body’s natural opioid system, which controls pain and reward responses. The results, the authors write in the study, “provide strong justification for further caution against widespread and repeated use of ketamine.” The study, which was led by researchers at Stanford University, was small and preliminary, and the results need to be replicated in future research. But if ketamine actually does work like an opioid, according to an [accompanying editorial](https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.2018.18070800 "undefined"), patients who take the drug for depression could become addicted to or dependent on it, just as with [other opioids](http://time.com/5170231/the-opioid-diaries/ "undefined"). “We would hate to treat the depression and suicide epidemics by overusing ketamine, which might perhaps unintentionally grow the third head of opioid dependence,” writes Dr. Mark George, a professor of psychiatry, radiology and neuroscience at the Medical University of South Carolina, in the editorial. Previous research has suggested that ketamine eases depression by targeting the brain’s glutamate system, which is involved in memory and learning. But the researchers behind the new study wanted to test the drug’s effects on opioid receptors. To do so, they gave 12 adult patients with treatment-resistant depression a [placebo](http://time.com/5375724/placebo-bill-health-problems/ "undefined"), followed by a ketamine infusion. On another occasion, the same patients took ketamine, but only after first taking an opioid blocker. Seven of the 12 patients saw marked improvements in depression symptoms a day after taking ketamine and the placebo — but none of the patients saw similar-scale reductions in depression after first taking the opioid blocker, suggesting that ketamine may work, at least in part, by activating the opioid system. (Both groups experienced the dissociative, or hallucinogenic, effects of ketamine.) The results were so stark that the researchers — several of whom have financial ties to the pharmaceutical industry, including to companies working to find depression treatments modeled after ketamine’s effects — stopped the trial early, according to the paper. Ketamine isn’t the only [psychedelic drug potentially finding new life as a medical treatment](http://time.com/5278036/michael-pollan-psychedelic-drugs/ "undefined") for mental health disorders. Studies have suggested that [psilocybin](http://time.com/4586333/psilocybin-cancer-anxiety-depression/ "undefined") (a compound in psychedelic mushrooms) and [LSD](http://time.com/12428/lsd-therapy-lowers-anxiety-study-finds/ "undefined") could be used to treat anxiety and depression in some people. ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/5381387/ketamine-opioid/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/5381387/ketamine-opioid/"},"headline":"Ketamine May Ease Depression By Acting Like an Opioid, Study Suggests","datePublished":"2018-08-29T14:47:09.000Z","dateModified":"2026-02-23T21:17:14.899Z","description":"That could put patients at risk of addiction","url":"https://time.com/5381387/ketamine-opioid/","keywords":["Drugs","onetime","healthytime"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt22016aed2cf92797/698938f9457a525deed5f3cb/ketamine.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Jamie Ducharme","jobTitle":"Ducharme is a contributor to TIME.","url":"https://time.com/author/jamie-ducharme/"}],"articleSection":"Health","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt22016aed2cf92797/698938f9457a525deed5f3cb/ketamine.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"Ketamine, notorious club drug, shows promise as a treatment for depression, studies indicate","caption":"Ketamine, notorious club drug, shows promise as a treatment for depression, studies indicate","creditText":"Chicago Tribune—TNS via Getty Images","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/health/","name":"Health"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/drugs/","name":"Drugs"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/5381387/ketamine-opioid/","name":"Ketamine May Ease Depression By Acting Like an Opioid, Study Suggests"}}]},{"@context":"https://schema.org","@type":"VideoObject","name":"Could Psychedelic Drugs Treat Mental Illness?","description":"Scientists are experimenting with whether magic mushrooms could treat depression","thumbnailUrl":"https://cdn.jwplayer.com/v2/media/P4VRuNde/poster.jpg?width=720","uploadDate":"2016-05-18T17:29:59.000Z","contentUrl":"https://cdn.jwplayer.com/manifests/P4VRuNde.m3u8","embedUrl":"https://time.com/5381387/ketamine-opioid/","duration":"PT56S","potentialAction":{"@type":"SeekToAction","target":"https://time.com/5381387/ketamine-opioid/?jw_start={seek_to_second_number}","startOffset-input":"required name=seek_to_second_number"}},{"@context":"https://schema.org","@type":"VideoObject","name":"Michael Pollan on the Healing Power of Psychedelics","description":"Author Michael Pollan explored the therapeutic properties of psychedelics for his latest book, \"How to Change Your Mind.\" His research includes firsthand experiences with the drugs.","thumbnailUrl":"https://cdn.jwplayer.com/v2/media/Z7yskoOT/poster.jpg?width=720","uploadDate":"2018-05-16T15:00:51.000Z","contentUrl":"https://cdn.jwplayer.com/manifests/Z7yskoOT.m3u8","embedUrl":"https://time.com/5381387/ketamine-opioid/","duration":"PT4M20S","potentialAction":{"@type":"SeekToAction","target":"https://time.com/5381387/ketamine-opioid/?jw_start={seek_to_second_number}","startOffset-input":"required name=seek_to_second_number"}}] ```