The UK’s advertising regulator has imposed a sweeping ban on online adverts promoting prescription-only weight loss injections, marking a significant crackdown on what it described as a “wild west” culture in digital pharmaceutical marketing.
The Advertising Standards Authority (ASA) issued nine new rulings this week, setting out clear rules on how prescription weight loss drugs, including Wegovy and Mounjaro, may be presented. Under UK law, prescription-only medicines (POMs) cannot be advertised directly to the public. However, a Guardian investigation last year found widespread breaches by online pharmacies, with ads often skirting the rules through indirect promotion.
Under the new measures, online pharmacies can still mention weight loss injections on their own websites, but not on homepages or landing pages reached via external links. Terms such as “weight loss injections” or “weight loss pen” are now prohibited in adverts, and promotions must present such treatments as part of a broader service involving consultation and prescription.
The ASA has also banned imagery showing injection pens or vials, as well as links to pages where named prescription medicines are the only available option.
ASA chair Nicky Morgan said the changes were aimed at protecting vulnerable consumers: “Nothing’s so harmful as powerful prescription-only medicines.”
The enforcement action follows an AI-assisted monitoring sweep in August and September 2024, during which the ASA scanned 28 million online adverts across all sectors. Around 20,000 ads from 35 priority pharmacies were flagged this year, with roughly half relating to weight loss drugs. Common violations included direct naming of drugs, injection imagery, and ads for “weight loss consultations” that linked to pages offering only POMs — a loophole that has now been closed.
One high-profile breach involved a paid Instagram post from TV personality Gemma Collins promoting the weight loss service Yazen. The ad referenced NHS-prescribed medication, and Yazen’s website linked to articles describing her use of “GLP-1 weight loss injections,” putting it in direct violation of the rules.
Pharmacies found to be in breach will be told to amend or remove offending material. Persistent or uncooperative offenders could face further measures, including takedowns in coordination with online platforms, and referrals to the Medicines and Healthcare products Regulatory Agency (MHRA) or General Pharmaceutical Council (GPhC), which have powers to impose fines, initiate court proceedings, or sanction licences.
While the ASA said most companies complied when contacted, some failed to respond.
Experts welcomed the move but urged stronger penalties. Dr Piotr Ozieranski of the University of Bath suggested sanctions linked to company turnover and patient safety risks, while UCL’s Oksana Pyzik cautioned that celebrity endorsements still risk glamorising medical weight loss.
The ASA confirmed it will continue monitoring both corporate and influencer-led promotions, with further rulings expected in the coming months.
