Weight loss drugs could help people avoid getting addicted to alcohol, tobacco and drugs such as cannabis and cocaine, a study has found.
They could also reduce the risk of people already addicted to illicit substances having an overdose, ending up in hospital or dying, according to research published in the British Medical Journal.
Glucagon-like peptide-1 receptor agonists used to treat type 2 diabetes and obesity, such as Mounjaro and Ozempic, are thought to work by influencing the brain’s reward pathways in order to cut cravings. They help people feel fuller by mimicking the natural substance released after eating.
The US study analysed 606,434 US veterans with type 2 diabetes, who were monitored for up to three years. It found that GLP-1s reduced the risk of alcohol-related disorders in those with no history of substance use by 18% and of using cannabis (14%), cocaine (20%), nicotine (20%) and opioids (25%), compared with those on other sodium-glucose cotransporter-2 drugs also used to treat diabetes.
Weight loss drugs also reduce the risk of people already using substances from overdosing (39%), needing emergency help in A&E (31%) or dying (50%).
“This study adds to emerging research exploring whether GLP-1 medicines may influence brain pathways involved in reward and addiction”, said Prof Claire Anderson, the president of the Royal Pharmaceutical Society, which represents 35,500 UK pharmacists.
She added: “As this was an observational study, it is important to be clear that it does not show these medicines prevent or treat addiction. Further research, including clinical trials, will be needed to understand whether GLP-1 medicines have a direct effect.”
Gareth Jones, the director of corporate affairs at the National Pharmacy Association, said: “This is a significant study and shows that weight loss treatment may have potential to give important additional therapeutic benefits.
“More is being understood all the time around the long-term impact [of GLP-1s], but it is clear that weight loss treatment can have a positive effect on a range of health outcomes, for those patients who are eligible and really need it.”
But the NHS’s rollout of the drugs to obese people remains “painfully slow”, despite the huge problems obesity is causing, he added.
A separate study found most people who stop taking GLP-1s regain 60% of the weight they lost within a year, and eventually 75% of it, only shedding 25% of that weight in the long term.
The finding comes from a meta-analysis of 48 previous studies undertaken by experts at Cambridge University and published in the journal eClinical Medicine.
The gradual weight regain “means that 25% of the initial weight loss may be sustained in the long term. For an individual who had lost a fifth of their weight while on the drugs, this would correspond to a sustained weight reduction of around 5%”, the authors said.
About half of all users stop taking GLP-1s within a year and 75% have stopped after two years, likely due to side-effects, such as nausea, and the overall cost involved.
Meanwhile, two-thirds of patients taking the drugs hide that they are doing so from friends and family, as they fear being judged and seen as “cheats”, a survey found.
Simple Online Pharmacy surveyed more than 3,000 GLP-1 users. They found that 38% had been criticised for doing so. Of those, 79% were accused of taking “the easy way out” and 68% told to “just eat less and move more”.
