Why weight loss medicines are not advertised in the UK
UK law bans adverts for prescription only medicines aimed at the public. Three regulators enforce the rule together.
Prescription only medicines may not be advertised to the public in the UK. The ASA, MHRA and GPhC issued a joint enforcement notice in April 2025 and updated the notice on 23 September 2025. Naming a weight loss medicine in an advert is almost certainly a breach.
The law
- Human Medicines Regulations 2012, regulation 284: bans any advert likely to lead to the use of a prescription only medicine.
- Advertising code rule 12.12: prescription only medicines or treatments may not be advertised to the public.
Source: ASA, MHRA and GPhC.
What the enforcement notice says
- Using a brand name, a generic name or an active ingredient in a weight loss advert is almost certainly a breach.
- Terms such as weight loss injection, weight loss pen and GLP-1 are likely to be read as references to a prescription only medicine.
- Pictures of an injection pen with a medicine name will almost certainly be seen as promotion.
- An advert may promote the consultation, not the medicine.
- The notice names Mounjaro, Wegovy, Ozempic, Rybelsus, Saxenda, Victoza and Mysimba.
Sources: ASA, MHRA and GPhC, GPhC.
Who enforces
- ASA: monitors adverts, including with AI tools, and can have content and accounts removed.
- MHRA: can investigate and use statutory powers under the Human Medicines Regulations.
- GPhC: can act against a pharmacy, the owner and the superintendent pharmacist, and can open fitness to practise cases.
What this means for you
- Treat any social media advert for a named weight loss medicine with care.
- A safe service sells a consultation first. The medicine follows only if a prescriber agrees.
- Report a misleading advert to the ASA and an unsafe seller to the MHRA.
How GLP Index handles this
GLP Index is a price database. Price tables report what registered pharmacies charge, as data. Discount codes sit on separate pages which name no medicine and no dose. The editorial policy sets out the rules we follow.
Questions
Is advertising Mounjaro or Wegovy legal in the UK?
No. Prescription only medicines may not be advertised to the public. The rule covers brand names, generic names and active ingredients.
Can a pharmacy offer a discount on a named weight loss medicine?
The GPhC enforcement lead said adverts and special price offers should not be used for prescription only medicines.
Which adverts are covered?
Paid social media, organic posts, paid search, influencer marketing, affiliate adverts, websites, email and other media within the advertising code.
Why do GLP Index code pages not name a medicine?
Code pages list pharmacy discount codes without any treatment name or dose. Price tables sit on separate pages and report prices as data.
Official sources
Every rule on this page comes from the sources below. GLP Index checked each one on 8 October 2026.
- Advertising Standards Authority, MHRA and GPhC. Enforcement notice: advertising of prescription-only medicines used for weight management. 23 September 2025.
- General Pharmaceutical Council. GPhC joins forces with other regulators over advertising of weight management medicines. 11 April 2025, updated 25 February 2026.
More on UK rules
- GLP-1 medicines in the UK: which are licensed for weight loss
- Who can get weight loss medicine in the UK
- Weight loss injections on the NHS: who qualifies and when
- Buying weight loss medicine online: the UK rules
- MHRA safety advice for weight loss medicines
- Who regulates weight loss medicines in the UK
- UK weight loss medicine timeline: every key decision
- NHS vs private: what weight loss medicine costs in the UK
- All UK rules pages