GLP‑1 Agonists: A New Hope for Substance Use Disorders?

GLP‑1 agonists cause weight loss indirectly by slowing the movement of food through the stomach and intestines and directly by acting on GLP‑1 receptors in the brain to reduce appetite and cravings and induce a feeling of satiety. Now, there is encouraging evidence that their effect on craving and satiety may help to treat substance use disorders.

A study last year found that people using GLP-1s to lose weight also consumed less alcohol. National Institute on Drug Abuse Director Nora Volkow was a researcher in a study this year suggesting GLP‑1 agonists may prevent relapse of alcohol use disorder. The evidence suggests these drugs reduce the desire to drink.

Dr. Volkow also co-authored a study this year showing GLP-1s reduce the incidence and relapse of cannabis use disorder.

Anecdotal evidence is fueling research into whether GLP-1s can help people quit smoking. Some studies show GLP-1s may work better when combined with other smoking cessation drugs. Studies thus far are inconclusive, but clinical trials are in progress.

In February 2024, researchers from Pennsylvania State University reported that a small study showed GLP‑1 agonists reduced cravings in people with opioid use disorder (OUD) by 40 percent over three weeks. While some animal studies have yielded disappointing results, other animal studies show promise.

It’s easy to get excited about the potential impact of GLP-1s on treating substance use disorder, whether used alone or in combination with other drugs or therapeutic modalities. First, these drugs are widely prescribed by primary care and other clinicians and are available in community pharmacies. In contrast to Canada, Australia, and the U.K., where primary care clinicians provide methadone treatment for people with OUD, the U.S. federal government requires OUD patients to visit federally approved Opioid Treatment Programs (OTPs) for their daily dose of methadone. If GLP-1s effectively reduce opioid cravings, patients could obtain them from a clinician’s office, avoiding the stigma and dehumanization imposed by the current system. Even if GLP-1s only work with other medications for opioid use disorder (MOUD), they might reduce patients’ dose requirements and reliance on MOUD.

Second, many addiction specialists oppose abstinence-only treatment for substance use disorder. They argue that patients may view themselves as hopeless failures if they “fall off the wagon” and resume heavy substance use. Reports show that 12-step abstinence programs have only a 5 to 10 percent success rate. Some addiction researchers note that most people eventually outgrow their addictions without treatment and argue that treatment should focus on harm reduction and moderation management. GLP-1s are compatible with this approach. They reduce cravings and increase satiety without generating abstinence.

Finally, if the evidence shows that GLP-1s are effective for treating substance use disorder, imagine how they could help people concerned about their substance use manage it privately and avoid stigmatization. Health care consumers already use telehealth to purchase GLP-1s through retailers employing licensed practitioners in their states. It’s easy to envision people using telehealth in the privacy of their homes to access GLP-1s to moderate or quit using a substance. This could prevent many people from progressing to more severe forms of substance use disorder and their associated harms.

It’s too soon to tell if GLP‑1 agonists will become a new tool for treating substance use disorders. Researchers have only recently begun to explore this issue in depth. A new organization, the Center for Addiction Science, Policy, and Research, tracks and aggregates the evidence on its Substack site. Let’s hope the evidence fulfills the drug’s promise.