Who: The Advertising Standards Authority (ASA)
Where: United Kingdom
When: 9 July 2025
Law stated as at: 18 August 2025
What happened:
Earlier this year, the ASA, together with the Medicines and Healthcare products Regulatory Agency (MHRA) and General Pharmaceutical Council (GPhC) issued a joint enforcement notice, reminding marketers that ads for prescription-only medicines, specifically those used for weight loss, are prohibited. In its latest update on its work in this area, the ASA has announced that it has officially taken action against nine advertisers.
Advertising of prescription-only weight-loss medications has grown rapidly in recent months, with ads seen on just about every type of media. The ASA understands these types of weight-loss medications as key to the UK government’s plans to tackle obesity. Public awareness and interest in them has also grown in recent times as some celebrities have used or are using such medications.
The ASA emphasises that the action it is taking is not to regulate the medications themselves, recognising the role they play, but to protect consumers from irresponsible and illegal weight-loss prescription-only medication ads.
The ASA sees its rulings against such ads as key to its work in this area, to set a clear precedent for advertisers. The rulings establish that the following practices are all banned:
- Advertising named weight-loss medications (such as Wegovy, Mounjaro, Ozempic, Saxenda).
- Making claims and using images that indirectly advertise these medications.
- Making claims referring to “weight loss injections”, “weight loss pen”, “obesity treatment jab”, “GLP-1”.
- Using certain imagery in the context of an ad for a medicated weight-loss treatment, even when the treatments are not explicitly featured. This includes unbranded medical injection pens, partial images of a branded medical injection pen and images of vials of liquid.
The ASA has been using its AI-based Active Ad Monitoring system to assist it with investigating these ads and enforcing against them. In this latest update, the ASA says that of 10,000 medicated weight-loss treatment ads from high priority pharmacies (those complained about since December 2024 or identified as problematic by the Active Ad Monitoring system), only 80 were found to directly use or mention a named weight-loss medication name. This amounts to a more than 99% compliance rate for this specific element of the rules. The ASA says that this shows some improvement since its initial warning and enforcement notice from earlier in the year.
While the ASA is encouraged by this improvement in compliance, it is continuing to make the advertising of medicated weight-loss treatments a high priority, noting that the use of indirect references (such as images of injection pens, and references to GLP-1 treatments) are an ongoing concern. The ASA has further investigations underway, with additional rulings to come. Its focus has so far been on paid-for ads, but it is also monitoring organic content and other channels, taking action as needed. Additionally, it will continue to utilise its Active Ad Monitoring system, to check that advertisers are sticking to the rules, and taking action when they are not.
Why this matters:
The ASA has kept its word after making it clear in its earlier enforcement notice that it would take action against advertisers not following the rules in this area. While there has been some improvement in compliance since the ASA started its work, ads that do not comply, for example by including indirect references to these drugs, are still appearing on a regular basis. The ASA will continue to conduct monitoring sweeps, so to avoid enforcement action, advertisers of such products should closely review the ASA’s guidance and ensure that their ads comply with the rules.
