New treatment using naltrexone implants can reduce heroin dependency: Study

A new treatment using naltrexone implants could lead to a significant reduction in heroin dependency. According to the researchers responsible for a recent Norwegian study, this should have major implications for the treatment options offered to heroin-dependent patients.

Nowadays the most common way to become heroin-free is through treatment with methadone or Subutex. These substances resemble morphine and are also addictive, but reduce heroin use and criminality among patients.

The new treatment is targeted towards people who wish to overcome their heroin addiction without using other addictive substances. The researchers have been using naltrexone, a substance that works by completely blocking the effect of heroin and other morphine substances. This reduces the likelihood of overdose, physical dependency and other drug cravings.

"This blockage effect induces a feeling of calm and allows the patients to escape from their heroin addiction and stressful, drug-dependent lives. They are able to concentrate on getting a new start," explains Nikolaj Kunøe, who, with the help of Research Council funding, completed his doctorate on this topic at the Norwegian Centre for Addiction Research (SERAF) at the University of Oslo.

Satisfied users

Some 56 heroin-dependent patients who had undergone detoxification treatment and were particularly motivated to remain heroin-free took part in the study. Half of the participants were implanted with a total of 20 subcutaneous pellets containing naltrexone, which was gradually released from a saline solution with the aim of producing a six-month blockage effect. All the participants continued their normal follow-up treatments while the study was ongoing.

After six months, over twice as many in the group receiving naltrexone as in the control group (11 out of 23 as opposed to 5 out of 26) managed to refrain from using heroin and other morphine substances. Heroin use among those patients receiving naltrexone who did not manage to discontinue using heroin altogether was more than halved compared with their level of heroin use before they started treatment. In the control group the majority of patients relapsed to daily heroin use.

Satisfaction with the naltrexone implants was high. On a scale from 0 to 100 the participants gave the capsules a score of 85.

"Clear-cut findings"

Helge Waal, Professor emeritus at SERAF, would like to see the naltrexone implant included as one of the treatment options offered to heroin-dependent patients in Norway.

"Although this is a relatively small-scale study, the findings are so clear-cut that we think this should become an important treatment option for substance abusers."