Weight Loss Jabs: Know the Warning Signs and Avoid Unregulated Online Sellers

7 August 2026

New figures reported this week show the Medicines and Healthcare products Regulatory Agency (MHRA) has received Yellow Card reports covering more than 200 suspected deaths and over 18,000 severe adverse reactions possibly connected to GLP-1 weight-loss injections. Across all reports, the regulator has logged more than 150,000 suspected adverse reactions for this class of medicine.

The numbers are significant, but they need careful reading. A Yellow Card report does not mean a medicine caused the event. It records that someone suspected a possible link, and reports can be submitted by patients, carers or healthcare professionals.

The MHRA has been clear that GLP-1 medicines remain safe and effective for the overwhelming majority of the roughly 1.6 million adults in Great Britain estimated to have used them for weight loss, and that the risk of serious side effects is small.

We at Pharmacy Online believe the reports are a reminder of two things: that these are powerful prescription-only medicines that belong in a proper clinical pathway, and that patients should know the red-flag symptoms that mean they need urgent help.

The bigger risk: buying jabs outside the regulated system

The safety data has landed alongside a separate MHRA warning about a sharp rise in fake and illegally supplied weight-loss injections. Pens bought through social media sellers, unregulated websites or messaging apps may contain the wrong dose, the wrong drug or no active ingredient at all, and they come with none of the clinical checks that reduce the risk of harm.

Legitimate supply should always involve a clinical assessment. That means checking a patient's medical history, confirming the treatment is appropriate, giving clear guidance on dosing and side effects, and following up over time. Prescription-only medicines cannot lawfully be advertised to the public in the UK, and no reputable pharmacy will supply a weight-loss injection without an assessment by a prescriber.

What our Superintendent Pharmacist had to say:

“These medicines can offer real benefits when they are prescribed and monitored properly, and for most people they are safe. But they are not a lifestyle product to be bought on a whim from a stranger online. The reports to the regulator are a signal to take safety seriously, not to panic. Our message is simple: get a proper clinical assessment, never buy jabs from an unregulated seller, and learn the warning signs. If you have severe stomach pain that spreads to your back, do not wait, seek urgent medical help.”

Umar Razzaq, Superintendent Pharmacist, Pharmacy Online

Know the warning signs

Much of the recent attention has focused on pancreatitis (inflammation of the pancreas), with hundreds of suspected cases reported to the MHRA in 2025. The regulator, working with Genomics England through the Yellow Card Biobank, is now studying whether some people are genetically more likely to develop it while taking these medicines.

Anyone using a GLP-1 injection should seek urgent medical advice if they experience:

• Severe, persistent stomach pain that may spread to the back, sometimes with nausea and vomiting, which can be a sign of pancreatitis.
• Signs of dehydration or being unable to keep fluids down, particularly with ongoing vomiting or diarrhoea.
• Symptoms of gallbladder problems, such as sudden pain in the upper right abdomen, fever or yellowing of the skin or eyes.
• Any other severe or unexpected reaction after starting or increasing a dose.

Patients and healthcare professionals can, and should, report suspected side effects through the MHRA's Yellow Card scheme. Reporting is how safety signals are picked up, and it is what makes studies like the Biobank possible.