[Naltrexone in the treatment of addiction]

Naltrexone is a well-known opioid antagonist that has attracted increased attention with respect to new techniques in detoxification, methods for improving compliance, and new indications. Naltrexone 50 mg Revia recently obtained registration in Norway as a pharmaceutical product. A review of its pharmacological properties and documentation of clinical use is merited.

Basic neurobiological descriptions are cited from review publications. In addition, Medline, Embase and the Cochrane library have been searched for evidence-based evaluations.

The basic antagonist effect is proven beyond doubt. Clinical dosages give few and moderate side effects. The drug's two properties, blocking for exogenic opioid and modulating the endogenic opioid system, are both therapeutically useful. Its use in the treatment of heroin addiction is hampered by poor compliance; this might be improved by formulations with prolonged duration or by special therapeutic techniques. Usefulness in treatment of alcohol problems is documented but effect size is moderate and partly dependent on psychosocial therapeutic techniques. There is interesting but undocumented reports on usefulness with nicotine and cocaine addiction, with gambling problems, in impulsive behaviour and in several other areas.