Weight loss injections have led some people to be hospitalised due to side effects such as vomiting, diarrhoea and constipation, two Scottish hospitals announced this weekend.
In fact, the reported cases are likely to be tiny proportion of those actually needing hospital treatment for this issue, and the numbers may continue to rise as more people buy the medicines online, experts have warned.
“We are seeing an increasing number of people coming to hospital with complications from weight loss drugs,” said Dr Vicky Price, president-elect of the Society for Acute Medicine, which represents doctors treating urgent medical conditions. “It’s already impacting capacity.”
The problems are being caused by the relatively new class of weight loss drugs that includes semaglutide (sold as Wegovy, or Ozempic when used to treat diabetes) and Mounjaro.
The Times reported on Sunday that 16 people had been admitted to Scottish hospitals since April last year. However, one of the hospital trusts involved, North Lanarkshire health board, told i that it had not released an exact number of affected patients. The other hospital trust, NHS Greater Glasgow and Clyde, was asked for comment but was unable to respond in time.
But while UK figures on the problem have not been centrally collected, hospital doctors have reported increasing numbers of people attending emergency departments with problems such as vomiting or severe constipation, said Dr Price.
More alarmingly, Mounjaro was found to have contributed to the death of a 58-year-old North Lanarkshire nurse from pancreatitis, organ failure and septic shock, the BBC reported last week. The Mounjaro manufacturer, Eli Lilly, said patient safety was the company’s top priority.
So, how worried should people be about such side effects?
The medicines were developed to treat type 2 diabetes, as they promote release of the blood sugar hormone, insulin. But the drugs also act on the brain to suppress appetite, as well as on the gut to slow down food digestion, and the rate at which food moves from the stomach into the intestines.
The slower stomach emptying contributes to people feeling fuller for longer and so helps them eat less, but it can also cause nausea and vomiting. The effects on the gut can also cause constipation in some people and diarrhoea in others.
The medicines also come with a warning that they can in rare cases cause pancreatitis – inflammation of the pancreas – which may happen because they stimulate the pancreas to make more insulin. This is thought to be very rare and so the recent death is concerning, said Professor Alex Miras, an endocrinologist at Imperial College London. “We haven’t had deaths in the clinical trials,” he said.
By far the largest number of side effects seen with the drugs are those involving the gut, and these caused about 1 in 10 trial participants to stop taking the medicines. People getting the drugs at NHS weight loss clinics are advised how to minimise these effects, said Professor Miras. Recommended tactics include eating smaller, regular meals, and avoiding fatty or spicy food.
Adjusting the medication dose can also help. The weekly injections should be started on a low dose then raised month by month, but the schedule can be slowed down if necessary.
But the weight loss injections are not yet widely available on the NHS, apart from for people with diabetes. Many people are therefore buying them from online pharmacies, from about £150 a month.
People need to fill in an online form that is reviewed by a doctor, and some firms may offer further advice about symptom management, but many do not, said Sarah Le Brocq, co-founder of All About Obesity, a charity that campaigns to help people access treatment. There are thought to be at least 50 online pharmacies that offer the weight loss drugs.
If people with weight loss jab side effects go to hospital, they may be reluctant to tell staff about their medication use, said Dr Price. The problem is likely to only get worse, with adverts for online pharmacy services becoming increasingly prevalent, she said.
“They might come in with sickness and diarrhoea and they’re embarrassed that they might have not got it from legitimate sources,” said Dr Price. “Or they may have not been entirely truthful online. It’s really important for doctors to know about [their medication use].”
People with severe vomiting or diarrhoea may need rehydration treatment, while those with severe constipation may need enemas, said Professor Miras.
Professor Naveed Sattar, a heart specialist at the University of Glasgow, said it was hard to know how much of a problem the side effects are causing to hospitals until the NHS releases figures. “Given that perhaps hundreds of thousands of people are thought to be taking these medicines in the UK, mostly from private providers, the number at A&E is relatively small, but closer inspection of data is needed,” he said.
“It is also possible that if weight is being lost in many because of the drugs, the overall balance for clinical care is actually positive.”
