One in seven people using drugs not licensed for weight loss as 1.6 million in UK now on them

At least 1.6 million Britons have used weight loss jabs in the past year, but one in seven of those are using drugs not licensed for this purpose as demand skyrockets.

Weight loss drugs such as Wegovy and Mounjaro have soared in popularity, with many spending hundreds of pounds on purchasing the drugs privately in a bid to lose weight.

A survey of 5,260 people revealed to researchers at University College London that an estimated 3.3 million people would be interested in using weight-loss drugs over the next year.

While 2.9 per cent of people surveyed said they use GLP-1 medication to lose weight – which is an estimated 1.6 million people – 15 per cent of these people are using medication that is not licensed for this purpose.

Researchers warned using drugs “off-label” can pose safety risks if the medicines are accessed without appropriate clinical supervision.

One drug used “off-label” is Rybelsus, licensed in the UK for type 2 diabetes only. It uses the same active ingredient as Wegovy, but it comes as a daily oral dose instead of a weekly jab, explained Dr Leyla Hannbeck, CEO of the Independent Pharmacies Association, who was not part of the study.

“Some healthcare providers may prescribe Rybelsus for weight loss, but it is not currently licensed for that purpose, and the off-licence use should be under the supervision of a healthcare professional to ensure the suitability for the patient and correct dose and monitored treatment,” she told The Independent.

Nausea, vomiting, stomach cramps and diarrhoea are all side effects of the drug, but there is also a risk of taking an incorrect dose.

“If a patient takes several tablets there is a risk of overdose, which can potentially cause severe low blood sugar, an increase in the intensity of the side effects, and in some cases, pancreatitis,” Dr Hannbeck added.

Study authors also raised concerns that as demand increases, some people taking these drugs may not be adequately supervised.

Co-author Professor Clare Llewellyn at UCL said: “Weight-loss drugs like GLP-1 agonists could play an important role in improving the health of the nation. Our findings suggest many people are accessing these medications outside the NHS.

“This raises concerns about equity given the costs of these drugs, as well as the adequacy of supervision of treatment.”

Lead author Professor Sarah Jackson at UCL added: “Large numbers of people are taking these drugs outside medical supervision and there is wide potential for misuse. NHS prescribing data only captures a small part of the picture.”

For the study, published in BMC Medicine and funded by Cancer Research UK, researchers used data from the Smoking Toolkit Study, an ongoing monthly survey of adults in England, Wales and Scotland (but not Northern Ireland).

Survey participants aged 18 and over were also asked about their use of five medications: Mounjaro (containing tirzepatide), Ozempic, Wegovy, Rybelsus (all three containing semaglutide) and Saxenda (containing liraglutide).

Four out of five respondents taking medication solely for weight loss reported using Mounjaro, which first became available on the NHS through GP practices in June last year, as part of plans to roll the jab out to 220,000 patients over the next three years.

Only a handful of the jabs can currently be prescribed for weight loss on the NHS. The criteria for a prescription are also currently strict, despite at least 3.4 million patients being eligible for them on the NHS.

At the beginning of September, the cost of Mounjaro increased to up to £335 per dose, which led people to seek alternatives.

The Department of Health and Social Care (DHSC) has been contacted for comment.