MHRA Warns of Weight Loss Drug Side Effects

The Medicines and Healthcare products Regulatory Agency (MHRA) has reminded healthcare professionals to warn patients about common and serious side effects associated with glucagon-like peptide-1 receptor agonists (GLP-1RAs). 

Simultaneously, the House of Lords food, diet, and obesity committee declared a public health emergency on obesity and diet-related diseases and recommended a tax on on junk foods.

In a drug safety update, the MHRA said that GLP-1RAs are “effective and acceptably safe treatments” when used within their licensed indications, but carry risks like all medicines.

Five GLP-1RAs are licensed to treat type 2 diabetes mellitus and obesity: dulaglutide, exenatide, liraglutide, lixisenatide, semaglutide, as well as tirzepatide (Mounjaro), a dual GLP-1 and glucose-dependent insulinotropic polypeptide receptor agonist.

Semaglutide (Wegovy) is also licensed to reduce the risk of major cardiovascular events in patients with established disease.

The MHRA alert said that the drugs posed a risk of gastrointestinal side effects such as vomiting and diarrhoea for more than 1 in 10 patients, with possible complications including severe dehydration, kidney damage, and hospitalisation. Patients should be warned and also alerted to the risk of less common but serious effects such as hypoglycaemia, pancreatitis, and gall bladder disorders.

Alert for Signs of Misuse

Health Secretary Wes Streeting said weight loss drugs “have enormous potential” and could be “game changers in tackling obesity”. 

However, he cautioned in a statement, “These are not cosmetic drugs that should be taken to help get a body-beautiful picture for Instagram.” They should only be used responsibly and under medical supervision.

“They’re not a quick fix to lose a few pounds, and buying them online without appropriate assessment can put people’s health at risk.” 

Healthcare professionals were advised to be alert for signs of misuse and to report any adverse reactions via the Yellow Card scheme. 

Ban on Junk Food Ads Proposed

The report of the House of Lords enquiry, which opened in January, noted that two-thirds of adults are now overweight, of whom nearly half are obese. One in 5 children start primary school overweight or obese, rising to more than 1 in 3 by the time they leave.

“Unhealthy diets are the primary driver of obesity, with people in all income groups failing to meet dietary recommendations,” peers said. They acknowledged that “there has been an utter failure to tackle this crisis” so far despite nearly 700 wide-ranging policies to tackle obesity in England over the last 30 years.

Calling for a new strategy “to fix our broken food system”, members noted an increased interested in reducing obesity through drugs such as semaglutide, which are a targeted rather than a population measure. Halving obesity by 2030 using weight-loss jabs would cost £16.5 billion a year, and bring pressure on the NHS.

Instead it called on the government to implement a comprehensive new legislative framework including:

• Giving the Food Standards Agency independent oversight of the food system.
• Introducing a salt and sugar reformulation tax on food manufacturers, building on the success of the Soft Drinks Industry Levy (sugar tax), and considering using the revenue to subsidise healthier food.
  • Banning junk food advertising:
    1. After the 9pm watershed (already planned).
    2. In paid-for online ads in October 2025.
    3. Across all media by the end of the current parliament.
  • Commissioning further research into links between ultra-processed foods and adverse health outcomes, and review dietary guidelines accordingly.
• Exclude businesses deriving significant sales from less healthy products from any discussions on policy on food, diet, or obesity prevention.

Dr Sheena Meredith is an established medical writer, editor, and consultant in healthcare communications, with extensive experience writing for medical professionals and the general public. She is qualified in medicine and in law and medical ethics.