The online pharmacies selling weight-loss jabs inappropriately

Some online pharmacies are still failing to make adequate checks when prescribing weight-loss jabs.

The General Pharmaceutical Council has expressed concern about inappropriate prescribing after a Which? investigation into the sale of weight-loss jabs found wide variation in prescribing practices among online pharmacies.

We went undercover, posing as a patient seeking GLP1 (weight-loss jab) medication for the first time to test the prescribing processes of major online pharmacies.

We used a genuine weight (overweight BMI), but falsely claimed to have high blood pressure – an obesity-related condition that would make us eligible for the jabs. We did this to test whether any pharmacies would interrogate the false high blood pressure claim before issuing prescriptions. 

Superdrug, MedExpress, Voy and Zava all sent us weight-loss jabs based on false health information and a fake GP address, without seeking to verify this information first.

The jabs are licensed for use in weight loss in patients who have a starting BMI of 30+ (classed as obese). Patients who are overweight, but have a weight-related health issue – such as high blood pressure, diabetes or high cholesterol – are also eligible, according to the drug's licensing information, set by the Medicines & Healthcare products Regulatory Agency (MHRA).

The General Pharmaceutical Council (GPhC), which sets prescribing guidelines for pharmacies, says clinicians should not rely solely on information given by a patient and must 'take appropriate steps to confirm that the medicine is appropriate'.  

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Some pharmacies did challenge false information

We set out to test the prescribing processes of a range of popular pharmacies. Some did flag false information early on, or require proof of qualifying health conditions.

Boots, Numan, Morrisons and Pharmacy2U refused to give us a consultation without genuine GP details.

Simple Online Pharmacy and MyJuniper didn't flag our fake GP address, but did require proof of high blood pressure to proceed.

Simple Online Pharmacy contacted us, requesting evidence of the condition, which it stated could be a GP letter confirming the condition, medication packaging with the label showing the date, name and address or a screenshot of a prescription for high blood pressure medication.

MyJuniper also required documentary evidence to confirm the medication was 'clinically appropriate and safe'.

What you need to know about weight loss jabs and supplements – listen to our health and wellbeing podcast for insight from our experts

Regulator concerned by Which? findings

We shared our findings with the GPhC, which said it was ‘concerned about the inappropriate prescribing of weight-management medications found by Which?' and 'will consider these findings as part of our ongoing review of emerging issues and risks in this area'.

We also reached out to the pharmacies that allowed us to order jabs based on false information for comment.

Superdrug told us its clinician ‘made a prescribing decision using their clinical judgement based on the information provided by the patient’.  

Zava said patient safety was ‘paramount’ and it relied on the ‘integrity and honesty of our patients when they provide personal health information'. Zava also stated that providing false information was a breach of terms. 

We first went undercover in 2024 to test weight-loss jab prescribing practices. At the time, the market was in its relative infancy, and we found we could proceed with online consultations for several pharmacies by providing a false weight. 

Verification processes for weight have tightened considerably since, with the GPhC issuing fresh guidance. Pharmacies now require photos of patients either in tight clothing or with a bare midriff to show their body composition.

But our most recent findings show that some pharmacies are still more lax about checks than others.

Rules left open to interpretation 

Our investigation revealed varied interpretations of weight-loss jab prescribing rules, with some pharmacies apparently routinely prescribing the medication ‘off label’ without requiring evidence of health-related conditions at all.

MedExpress, which didn’t respond to our requests for comment, states on its website that, where ‘safe and appropriate’, it will ‘in some cases’ prescribe to people with a BMI of between 25 and 30 (classed as overweight rather than obese). 

Voy, in response to our findings, told us it prescribes to people with a BMI as low as 25 as standard. 

It stated that anyone with a BMI of 25+ qualifies for jabs, even without a health-related condition, because it takes a 'proactive approach to health'. The company added that it was compliant with the regulations.

'Off-label' prescribing is relatively common in medicine. It means a clinician can prescribe a medicine where appropriate and justified, even if it’s not intended for that specific use.

No specific guidance exists for off-label prescribing of weight-loss jabs. Clinicians, however, are meant to exercise extra caution when prescribing off-label. 

Weight-loss ads also found breaking the rules

Because weight-loss jabs are medicines, companies can't directly advertise them to consumers. However, they can advertise general weight-loss services, which creates a grey area. And in recent years, many have fallen foul of advertising rules. 

The Advertising Standards Authority (ASA) analysed 35,000 online weight loss ads between February 2025 and January 2026 (including social posts) from 44  pharmacies and found that 900 broke the rules. The ASA said compliance across the sector was generally high – more than 97%, but that still leaves many hundreds of ads that failed to comply.

Dr Marie Spreckley, from the University of Cambridge’s Epidemiology Unit, told us that weight-loss jabs are an ‘important and effective tool', but warned that they're clinical medicines, not consumer products. She said:

'There is growing concern that the distinction between prescription medicines and consumer products is becoming blurred. The way these medications are discussed on social media and in some commercial settings can make them seem like quick, simple solutions.

This risks underplaying the clinical nature of these treatments, their potential side effects and the need for medical oversight.'

Find out more about the pros and cons, and hear from Which? members who have used the drugs in our guide to weight-loss jabs.