Some patients taking the weight-loss drug Mounjaro have told BBC News they are struggling to obtain the medicine, and are worried about the impact on their health.

There is rising demand for the drug, after the US manufacturer Eli Lilly announced a major price increase from 1 September.

The drug giant has warned against “inappropriate stockpiling of medicines” and has now asked UK distributors to stop taking orders from pharmacies from the end of today.

Pharmacies say they are prioritising patients already taking the drug, rather than those just starting it, and predict supplies will return to normal in early September.

Lynne Massey-Davis, 65, from East Yorkshire, says trying to find Mounjaro stock has been “stressful” after her last prescription order with an online provider wasn’t delivered.

“I’m in a holding queue,” she said. “It’s a very uncertain time. I’ve spent a lot of time on the phone.”

She’s been told there will be a two-week delay on delivery. In the meantime, she paid £349 to another provider who then said they too had run out, which she describes as “unethical”.

Fifteen months ago when Lynne started taking the weight-loss drug, she had a BMI of 32. Now it’s down to 26 and she “feels 10 years younger”, regularly doing park runs, going swimming and walking her dogs.

“I’m worried about my health but I will stay safe. There may be many others who will not.”

Lynne is planning to share a friend’s doses until her order arrives.

The National Pharmacy Association (NPA), which represents 60% of community pharmacies in the UK (around 6,500), said there had been “an increase in demand” for Mounjaro ahead of the planned September price hike.

Eli Lilly has announced the drug’s price will rise by up to 170%, meaning a month’s supply of the highest dose will go up from £122 to £330.

The company said the drug had been sold in the UK at a price that was “significantly below” that charged in other European countries. US President Donald Trump had previously complained about the high cost of drugs in the US.

“This increase in the cost of Mounjaro has caused understandable concern to patients and pharmacies alike and has resulted in short term pressures on supply,” said NPA chief executive Henry Gregg.

He urged patients to avoid bulk ordering Mounjaro because “it can have a significant impact on supply and pose a potential risk to patient safety”.

“We’d also urge patients to avoid unlicensed sellers, who may be selling fake medication or medication that does not meet UK safety standards,” he added.

Instead, he encouraged patients to speak to their local pharmacy for advice.

One provider, Chemist4U, said supplies of Mounjaro were “a bit restricted” and they were holding back stocks for existing patients who were preparing to up their dose.

“We envisage supplies to return back to normal once Eli Lilly release new stock after 1 September,” said CEO James O’Loan.

Sehar Shahid, who runs 24hrpharmacy.co.uk in Paisley, said her advice to people was not to panic and start bulk buying “because that makes it worse for everyone”.

She also said switching to other, alternative weight-loss drugs like Wegovy should only be done under medical supervision, and after a wash-out period because the drugs don’t work in exactly the same way.

Her advice is to speak to your provider, find out all your options, keep up healthy habits like exercising and healthy eating – but warns not to turn to influencers on social media for advice.

“These drugs are not for people who want to lose a few pounds before their holiday,” she adds.

Marie Cook, 49, from east London, who is prescribed Mounjaro on the NHS to treat her type 2 diabetes contacted Your Voice, Your BBC News to say she was also running out of the drug.

“I’ve been taking it for a year, come off insulin and lost 3.5 stones but have just got one week’s injections left.”

Her local chemist returned her prescription and she’s tried six others, but none have the drug in stock.

“It’s frustrating. We have true medical problems, we should come first,” Marie says.

She’s hoping a visit to her diabetic nurse on Monday will help.

Eli Lilly told BBC News it has allocations in place for pharmacies and providers that order stock from them.

“There are legal protections in place, enforced by the MHRA [UK drugs regulator], to prevent inappropriate stockpiling of medicines by providers. 

“We encourage patients to only order based on their current treatment plan, to reduce the risk of localised disruption.”