Semaglutide (the active ingredient in Ozempic and Wegovy) and other GLP-1 medications have rapidly become some of the most popular drugs in the world. Originally developed for type 2 diabetes, GLP-1s are now better known for treating obesity. In the near future, though, these drugs could have yet another vital use as treatments for alcohol addiction and other substance use disorders.

Over the past few years, a growing base of evidence has suggested that GLP-1s can tamp down people’s unhealthy urges for alcohol, cocaine, and even vices like gambling. And earlier this month, researchers in Denmark published data from the first double-blinded, randomized, and placebo-controlled trial of semaglutide for alcohol use disorder in The Lancet. Over a 26-week period, the study found that people on semaglutide consumed less alcohol than those given a placebo and experienced noticeably fewer heavy drinking days when they did drink.

There are other similar studies underway, including in the United States. Some are testing semaglutide for other kinds of substance use disorder, like opioids. Others are testing newer drugs like tirzepatide (a dual agonist that pairs GLP-1 with the hunger-related hormone GIP).

I reached out to an outside expert, Asim Shah, a professor and executive vice chair of psychiatry and behavioral sciences at Baylor College of Medicine, to talk about the emerging science surrounding GLP-1s and addiction treatment. We discussed the leading theory behind why GLP-1s can reduce addiction, his opinion of the recent Lancet trial, and what it will take for these drugs to be widely adopted as treatments for substance use disorders. The following has been lightly edited for clarity and grammar.

Ed Cara, Gizmodo: Do we have any sort of sense yet as to how or why GLP-1s seem to be working well against substance use disorders?

Asim Shah: So the craving, or pleasure, center of the brain is related to dopamine, which is a brain neurotransmitter. Whenever you crave something and you eat it or you take it, that gives you pleasure. That is the dopamine functioning in the brain. And all of this is related to the same thing, whether it’s a craving for food, craving for smoking, craving for alcohol, any drug. That’s the neurobiological mechanism of craving and pleasure, and it’s all the same mechanism.

And incidentally, we found out that the people who were losing weight on these GLP-1s, they often also stopped smoking cigarettes and their addiction got better with alcohol. It was an incidental finding, but it’s something people are now trying to study more closely.

Gizmodo: Speaking of studies, what do you make of the newest trial published in The Lancet this month?

Shah: So this was a 26 week study, which had about 100 patients, half and half men and women both. In our world, 100 patients is a medium sized study; a larger one might usually have 300, 400, 600 patients. So this is a medium sized study, which is decent. It’s not bad. And in my opinion, it was done pretty well, not a lot of bias in the study that I saw.

Now, of course, this is not a definitive study. And you need to follow up with these patients after the weeks of study. We call these start-up studies, and they are what we base future, longer and bigger studies on. So it’s a good base, and there are other studies on the way.

Gizmodo: Broadly speaking, what are the questions that these longer and larger studies need to try answering?

Shah: So there are a couple of things.

These are different substances that people are looking at; one is alcohol, one smoking, the other is opiates. So the next studies we should be doing is to see whether GLP-1s like semaglutide can limit more than one of these addictions. Because the mechanism is the same mechanism for all the cravings and the addictions. So can it reduce all of these or just one if somebody is taking it?

If we do keep seeing an effect here, it’s also important to know how quickly this happens and whether it can be sustained after you stop using a GLP-1. That’s why we have to follow people after these sorts of trials, to see if the effect can last after they stop taking the medication or if it requires people needing to stay on the drug for the effect.

Gizmodo: These sort of studies are happening. But what should be the current takeaway for people with these addictions and their doctor? Is this something that could be used in the real world right now?

Shah: Because they’re not approved right now, the takeaway should be that if you already have a current indication to take a GLP-1 which is for diabetes or obesity, certainly take it. If you also get an added advantage of stopping your smoking or alcohol use disorder, that is well and good because we don’t have approval for these disorders currently.

So in other words, if somebody comes to us and says, “Hey, I want to start these medicines for smoking cessation or alcohol use disorder,” we may not be able to prescribe it because there’s no approval. But they can be part of a study which is going on in some centers for those disorders. And if somebody already is using them for diabetes or so, and in addition, they get a benefit for alcoholism, that’s great, too.