A new study has found that varenicline, a medication commonly used to help people quit smoking, may also help reduce cannabis use in people with cannabis use disorder (CUD)—but only in men.
The research, published in the journal Addiction, offers new hope in tackling a growing problem, as CUD becomes more common due to widespread legalization of cannabis in many countries and US states.
Cannabis use disorder is a condition where people continue using cannabis even though it causes serious problems in their lives. These problems might include missing work or school, ignoring responsibilities, or continuing to use cannabis despite health issues.
CUD has also been linked to conditions like psychosis, poor sleep, withdrawal symptoms, and mood or anxiety disorders. Currently, there are no approved medications to treat CUD, making this discovery especially important.
The study was conducted at the Medical University of South Carolina and involved 174 participants who used cannabis at least three times a week.
Participants were randomly assigned to receive either varenicline (up to 1 mg twice a day) or a placebo for 12 weeks. All participants also had weekly check-ins with healthcare staff to help them stay on track with the treatment plan.
The researchers found that men who received varenicline reduced their cannabis use significantly more than those who received the placebo. On average, the men in the varenicline group used cannabis 7.9 times per week during the study and 5.7 times per week in the week after the study ended.
By comparison, men in the placebo group used cannabis more than 12 times per week. The varenicline group also used cannabis on fewer days per week—3.8 days versus 4.7 days in the placebo group.
In contrast, the drug did not appear to help women reduce their cannabis use. Women taking varenicline reported using cannabis just over 10 times per week during the study, compared to 9.2 times for the placebo group, and 8.2 in the week after the study.
They also reported using cannabis on more days per week than women in the placebo group. In fact, women taking varenicline experienced more withdrawal symptoms, stronger cravings, and higher levels of anxiety than any other group in the study. These effects may have made it harder for them to stick with the treatment.
Lead researcher Professor Aimee McRae-Clark explained the importance of these findings. “Cannabis use disorder is rising quickly in the United States, and our options for treating it are very limited,” she said. “This study shows that varenicline may be useful in reducing cannabis use, at least for men.”
She emphasized the need for further research, especially to understand why varenicline did not help women in the same way. “Our next step is to test varenicline in a larger group of women, so we can better understand the sex differences in response to treatment,” she said.
For now, the findings are encouraging. If future studies confirm the results, varenicline may become one of the first medications shown to help with cannabis use disorder. That could make a big difference for people struggling to cut back on cannabis and improve their quality of life.
If you care about smoking, please read studies about smoking may increase heart disease risk by 200% and e-cigarette smoke may cause lung cancer and bladder disease.
For more health information, please see recent studies about the cause of weight gain after smoking cessation, and results showing smoking may cause white scars on the brain.
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