A U.S. government-funded study has provided evidence of a hopeful treatment for people struggling with methamphetamine use. People given a combination therapy of medications were more likely to avoid the drug and report improvements to their life than those given standard support and placebo, the study found. The findings are all the more encouraging because methamphetamine use disorder is especially hard to treat.
In recent years, the drug overdose crisis has only worsened. There were more than 70,000 overdose-related deaths in 2019, and it’s strongly expected that 2020 was worse, thanks in part to the covid-19 pandemic. Much of the focus on the crisis has been paid to opioids, but it’s become apparent that abuse of other drugs — including stimulants like methamphetamine — is also on the rise.
While it’s difficult for many people struggling with drug addiction to find help, there are available treatments for opioid use and alcohol use disorder, as well as for quitting smoking. These include medications that reduce craving and withdrawal symptoms that can be paired with counseling and therapy. To date, however, there are no medications known to reduce these symptoms for meth use specifically.
This new study, published Wednesday in the New England Journal of Medicine, tested out a combination of two medications: bupropion, an antidepressant and smoking cessation aid, as well as naltrexone, used to help treat opioid and alcohol use disorder.
The trial involved 403 volunteers with moderate-to-severe methamphetamine use disorder who were randomised into the treatment group or placebo. A second round of the trial, involving people in the placebo group who didn’t respond to treatment, was conducted with 225 volunteers. Those in the treatment group were given an injection of naltrexone every three weeks and a daily pill of bupropion, then they were monitored for six weeks. Participants in both groups met with clinicians weekly and received counseling; they also had their urine tested for meth.
Across the two trials, the percentage of people who responded to treatment (defined as testing negative for meth at least three out of four times) was low for both groups. But it was noticeably higher for people on the medication combo. On average, 13.6% of those taking bupropion and naltrexone responded to treatment, compared to 2.5% of people on placebo. In surveys the volunteers took, those in the experimental group seemed to report fewer cravings and a greater improvement in life quality over the trial length, though the researchers caution that these findings are less certain. There were no serious adverse effects linked to the treatment, but users did show a higher risk of nausea, vomiting, and constipation compared to the placebo group.
The benefits of this combination therapy are likely modest at best. But the authors note that the level of improvement seen in this study is roughly similar to other established treatments for some mental health and substance use disorders, including an unhealthy alcohol dependence. If nothing else, it could represent the first evidence-based medication for methamphetamine use disorder, a serious illness that can lead to long-term health complications like heart and brain damage, as well as hallucinations, paranoia, and severe tooth decay and loss.
“This advance demonstrates that medical treatment for methamphetamine use disorder can help improve patient outcomes,” said Nora Volkow, director of the US National Institute on Drug Abuse, which helped run the study, in a statement released by the federal agency.
Though the study does pave the way for this combination therapy to be used widely for these patients, future studies will have to test out how effective it can be in more real-world settings and for longer periods of time, the authors wrote.