Psych · Addiction psychiatry — substance use disorders
Opioid substitution therapy and withdrawal
Also known as Opioid agonist treatment · OAT · OST · MOUD · Methadone maintenance · Buprenorphine induction · Opioid withdrawal · COWS · Medication for opioid use disorder
Fellowship-depth leaf on opioid withdrawal and substitution: COWS, detoxification, methadone and buprenorphine induction and maintenance, QTc, naloxone, naltrexone, pregnancy, and retention-mortality evidence. FRANZCP-primary, globally tagged.
Checked against its sources on 23 Oct 2026
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Red flags
- In severe respiratory depression, restoration of ventilation and oxygenation takes precedence over the history, examination or diagnostic testing
- Methadone levels accumulate over the first several days, and deaths have occurred in early treatment due to the cumulative effects
- Any patient who has not taken opioids for more than 5 days may no longer be tolerant to methadone
- The induction phase onto methadone and the time immediately after leaving treatment are periods of particularly increased mortality risk
- If the QTc interval exceeds 500 ms on methadone, consider discontinuing or reducing the dose or using an alternative therapy
Meet the patient
A 38-year-old on methadone 80 mg daily is admitted after a fractured femur. The surgical team holds his dose and prescribes paracetamol. By day 2 he is soaked in sweat, vomiting, restless, with dilated pupils, and described in the notes as "drug-seeking".[19]
Why the examiner cares. The methadone label lists the opioid withdrawal signs he is showing, including lacrimation, rhinorrhoea, yawning, excessive perspiration, goose-flesh, restlessness, dilated pupils, tachycardia, abdominal cramps, body aches, nausea, vomiting and diarrhoea.[19]
References22ShowHide
- [1]Mattick RP, Breen C, Kimber J, Davoli M Methadone maintenance therapy versus no opioid replacement therapy for opioid dependence Cochrane Database Syst Rev, 2009.PMID 19588333
- [2]Mattick RP, Breen C, Kimber J, Davoli M Buprenorphine maintenance versus placebo or methadone maintenance for opioid dependence Cochrane Database Syst Rev, 2014.PMID 24500948
- [3]Wesson DR, Ling W The Clinical Opiate Withdrawal Scale (COWS) J Psychoactive Drugs, 2003.PMID 12924748
- [4]Sordo L, Barrio G, Bravo MJ, Indave BI, Degenhardt L, Wiessing L, et al. Mortality risk during and after opioid substitution treatment: systematic review and meta-analysis of cohort studies BMJ, 2017.PMID 28446428
- [5]Lee JD, Nunes EV, Novo P, Bachrach K, Bailey GL, Bhatt S, et al. Comparative effectiveness of extended-release naltrexone versus buprenorphine-naloxone for opioid relapse prevention (X:BOT): a multicentre, open-label, randomised controlled trial Lancet, 2018.PMID 29150198
- [6]D'Onofrio G, O'Connor PG, Pantalon MV, Chawarski MC, Busch SH, Owens PH, et al. Emergency department-initiated buprenorphine/naloxone treatment for opioid dependence: a randomized clinical trial JAMA, 2015.PMID 25919527
- [7]Jones HE, Kaltenbach K, Heil SH, Stine SM, Coyle MG, Arria AM, et al. Neonatal abstinence syndrome after methadone or buprenorphine exposure N Engl J Med, 2010.PMID 21142534
- [8]Boyer EW Management of opioid analgesic overdose N Engl J Med, 2012.PMID 22784117
- [9]Gowing L, Farrell M, Ali R, White JM Alpha₂-adrenergic agonists for the management of opioid withdrawal Cochrane Database Syst Rev, 2016.PMID 27140827
- [11]Krantz MJ, Martin J, Stimmel B, Mehta D, Haigney MC QTc interval screening in methadone treatment Ann Intern Med, 2009.PMID 19153406
- [12]Minozzi S, Amato L, Jahanfar S, Bellisario C, Ferri M, Davoli M Maintenance agonist treatments for opiate-dependent pregnant women Cochrane Database Syst Rev, 2020.PMID 33165953
- [13]Larochelle MR, Bernson D, Land T, Stopka TJ, Wang N, Xuan Z, et al. Medication for Opioid Use Disorder After Nonfatal Opioid Overdose and Association With Mortality: A Cohort Study Ann Intern Med, 2018.PMID 29913516
- [14]Degenhardt L, Randall D, Hall W, Law M, Butler T, Burns L Mortality among clients of a state-wide opioid pharmacotherapy program over 20 years: risk factors and lives saved Drug Alcohol Depend, 2009.PMID 19608355
- [15]Weiss RD, Potter JS, Fiellin DA, Byrne M, Connery HS, Dickinson W, et al. Adjunctive counseling during brief and extended buprenorphine-naloxone treatment for prescription opioid dependence: a 2-phase randomized controlled trial Arch Gen Psychiatry, 2011.PMID 22065255
- [16]Fudala PJ, Bridge TP, Herbert S, Williford WO, Chiang CN, Jones K, et al. Office-based treatment of opiate addiction with a sublingual-tablet formulation of buprenorphine and naloxone N Engl J Med, 2003.PMID 12954743
- [17]National Institute for Health and Care Excellence Drug misuse in over 16s: opioid detoxification (CG52) NICE clinical guideline CG52, 2007.Source
- [18]National Institute for Health and Care Excellence Methadone and buprenorphine for the management of opioid dependence (TA114) NICE technology appraisal TA114, 2007.Source
- [19]US National Library of Medicine DailyMed METHADONE HYDROCHLORIDE TABLET [AMERICAN HEALTH PACKAGING] DailyMed, 2026.Source
- [20]US National Library of Medicine DailyMed SUBOXONE (BUPRENORPHINE HYDROCHLORIDE, NALOXONE HYDROCHLORIDE) FILM, SOLUBLE [INDIVIOR INC.] DailyMed, 2026.Source
- [21]US National Library of Medicine DailyMed NALOXONE HYDROCHLORIDE INJECTION [DR. REDDY'S LABORATORIES, INC.] DailyMed, 2026.Source
- [22]US National Library of Medicine DailyMed VIVITROL (NALTREXONE) KIT [ALKERMES, INC.] DailyMed, 2026.Source
- [23]US National Library of Medicine DailyMed LUCEMYRA (LOFEXIDINE HYDROCHLORIDE) TABLET, FILM COATED [USWM, LLC] DailyMed, 2026.Source