Naltrexone in prevention of alcohol relapse

• there is evidence that naltrexone is effective for preventing the recommencement of alcohol consumption in patients with alcohol dependence
  • a systematic review revealed that naltrexone may reduce the risk of treatment withdrawal in the short-term (1). The review concluded that naltrexone may be beneficial, in conjunction with intensive psychosocial treatment, in the medium and long term
  • a randomised controlled trial comparing medical management with 16 weeks of naltrexone (100 mg/d) or acamprosate (3 g/d), both, and/or both placebos, with or without a combined behavioral intervention (CBI). A further group received CBI only (no pills). Patients were also evaluated for up to 1 year after treatment (2)
    • patients receiving medical management with naltrexone, CBI, or both fared better on drinking outcomes, whereas acamprosate showed no evidence of efficacy, with or without CBI. No combination produced better efficacy than naltrexone or CBI alone in the presence of medical management. Placebo pills and meeting with a health care professional had a positive effect above that of CBI during treatment
• practical aspects of use of naltrexone in alcohol dependence (3)
  • duration of treatment is 3 months though evidence for longer term use is currently being evaluated. There may be continued benefits after stopping drinking
  • side effects include nausea, headache, requirement for analgesia, dysphoria, hepatotoxicity (therefore LFTs need to be checked at 3 months) (3)
  • a warning card should be given for the patient to carry to warn emergency healthcare teams of opiate blockade. Psychosocial interventions such as cognitive behavioural therapy and/or coping skills are an essential component for efficacy of this medication
  • prescribing of this medication should be discussed with an addiction specialist
    
    
  • NICE state that (4):
    • if using oral naltrexone, start treatment after assisted withdrawal
      • start prescribing at a dose of 25 mg per day and aim for a maintenance dose of 50 mg per day. Draw the service user's attention to the information card that is issued with oral naltrexone about its impact on opioid-based analgesics
      • oral naltrexone should:
        • usually be prescribed for up to 6 months, or longer for those benefiting from the drug who want to continue with it
        • be stopped if drinking persists 4-6 weeks after starting the drug

Service users taking oral naltrexone should stay under supervision, at least monthly, for 6 months, and at reduced but regular intervals if the drug is continued after 6 months. Do not use blood tests routinely, but consider them for older people, for people with obesity, for monitoring recovery of liver function and as a motivational aid for service users to show improvement. If the service user feels unwell advise them to stop the oral naltrexone immediately. The advice concerning monitoring of liver function differs from the RCGP who state that LFTs need to be checked at 3 months (3)

Reference:

• (1) Srisurapanont M et al. Opioid antagonists for alcohol dependence. Cochrane Database Syst Rev 2005; (1): CD001867
• (2) Anton RF et al. Combined pharmacotherapies and behavioral interventions for alcohol dependence: the COMBINE study: a randomized controlled trial. JAMA. 2006 May 3;295(17):2003-17.
• (3) SMMGP (February 2010). Network;28:12-14.
• (4)NICE (February 2011). Alcohol-use disorders - Diagnosis, assessment and management of harmful drinking and alcohol dependence