Group/Indications:
Narcotic Analgesic, Antagonist.
Narcotic (opioid) analgesics are medications of natural (plant and animal), semi-synthetic, and synthetic origin, which possess significant pain-relieving effects, primarily affecting the central nervous system (CNS), and have the potential to cause psychological and physical dependence (addiction).
Indications:
Opioid addiction (as an auxiliary medication after the withdrawal of opioid analgesics)
Alcoholism
Opioid Dependence:
Naltrexone and other opioid receptor antagonists are the drugs of choice for treating opioid dependence in countries where legislation prohibits the use of opioid agonists for this purpose.
However, several studies have not shown a tendency for patients receiving naltrexone to stop using opiates; in most studies, the results were no better than those with placebo. For example, a meta-analysis of 13 randomized controlled trials of oral naltrexone (1158 participants) did not demonstrate any advantage of this drug over placebo for both the treatment of opioid dependence and the prevention of relapses.
Nevertheless, a meta-analysis covering 10 studies showed the effectiveness of naltrexone combined with psychosocial therapy; this combination was more effective than placebo in reducing heroin use and re-incarceration during treatment.
It has been noted that one of the main problems in treating opioid dependence with naltrexone is low adherence to treatment: the levels of compliance and retention on the drug are low, and usually, the dropout rate in studies is extremely high. Many studies report a high number of cases where naltrexone treatment was discontinued within the first few weeks. For instance, Rothenberg reported that only slightly more than half of the participants completed four weeks of naltrexone treatment combined with behavioral therapy. Greenstein et al. reported that 47% of opioid-dependent patients discontinued treatment within the first few weeks. Moreover, according to Tennant et al., more than a quarter of their patients discontinued the study within a few days. Rothenberg also reported even more unfavorable results—only 39% adhered to treatment for a month, and none of the patients completed the six-month course.
Naltrexone is also used for rapid detoxification (i.e., quick alleviation of withdrawal symptoms), where it is combined with clonidine, lofexidine, buprenorphine, or methadone, and for ultra-rapid detoxification, where anesthetics are added to this combination. The effectiveness and safety of rapid detoxification have been proven. Ultra-rapid detoxification is a highly controversial method due to the medical risks and mortality risks associated with anesthesia compared to the painful but generally non-lethal opioid withdrawal without treatment.
