Weight loss jabs could be a new weapon in the battle against drug addiction, quelling cravings for powerful narcotics as well as calories.

The injections, including Wegovy, are being offered on the NHS to people who are obese via specialist weight management services.

Now, a US study suggests the relatively cheap treatment could be as effective at helping addicts ditch opioid drugs as £800-a-night rehabilitation centres.

Patients treated with liraglutide reported that their cravings were cut by 40 percent, compared with those given a dummy dose.

Study leader Professor Sue Grigson, director of the addiction centre at Penn State College of Medicine in the US, said the work was based on the idea that some people are more vulnerable to addiction than others.

She said: “They’ll do anything, basically, to get the drug. They’ll not take care of themselves or their family, they’ll take big risks.

“We started to think about that as being driven by need – something like a desperate need for food, water or salt.

“So that’s what led us to GLP-1. It’s a satiety agent that is able to reduce motivated behaviour for ‘needed’ substances.”

Wegovy and Ozempic are both semaglutide-based drugs that mimic the GLP-1 hormone, released in response to eating. The trial used a similar drug, liraglutide, which is cheaper and taken more frequently.

The study involved 20 people who had mostly been taking fentanyl, a synthetic opioid up to 50 times more potent than heroin.

One week into withdrawal, half started taking liraglutide while the rest received a placebo. All were questioned about their urges for three weeks.

The average craving score on a four-point scale was 0.9 for those given liraglutide, compared with 1.5 for the placebo group.

Researchers said the drop was about what they would expect if a person attended an intensive rehabilitation centre for two weeks.

Those who received the treatment reported that their cravings increased less during the day, and they were less likely to feel the urge to use drugs when stressed.

Some of those using the diet medication even reported periods where they felt entirely free of any urge to use opioids.

Prof Grigson added: “That was surprising. We were really excited to find that there could be any time in anyone’s day that early in treatment, within days of starting their recovery when they might say, ‘No, I’m actually not craving this at all.’”

Some patients experienced gastrointestinal problems and nausea, so researchers are planning further research using semaglutide, which may cause fewer side effects.

Fentanyl and other synthetic opioids were involved in the majority of more than 100,000 drug overdose deaths recorded in the US during the year to May 2023.

The UK has not faced such a widespread crisis, although the drugs have been linked to spikes in drug-related deaths in England in 2017, 2021 and 2023.

A government report last year warned “they may become much more prevalent” and urged local councils to begin preparing.

Prof Grigson added: “This work started because of the huge increase in overdose deaths due to opioids, which have accelerated following Covid.

“In the United States, we’ve lost over 112,000 people this past year – that’s one person every five minutes.

“We have a real sense of urgency as a consequence of that. Some of us on the research team have lost people. That pushes us.”

Scott Bunce, associate professor of psychiatry at Penn State University, who co-led the study, said the trial was small but “very encouraging”.

He added: “The safety profile of this class of medication has been tested in thousands of individuals, and is well known.”

The findings were presented at the American Association for the Advancement of Science’s annual conference in Denver, Colorado.