Eli Lilly, Semaglutide and the Confusion Worth Clearing Up

The misconception: why so many people search for 'Eli Lilly semaglutide'

It is easy to see how the confusion takes hold. Weight-loss injections have been widely covered in the UK press, and the names Eli Lilly, Novo Nordisk, Mounjaro, Wegovy, Ozempic and semaglutide tend to appear together in the same articles. Readers absorb a cluster of terms without necessarily catching which company makes which drug.

The short answer: Eli Lilly does not make semaglutide. Semaglutide belongs entirely to Novo Nordisk. What Eli Lilly makes is tirzepatide, the active ingredient in Mounjaro, a related but distinct medicine. Both companies compete in the same market, which is part of why their names get tangled.

A question our prescribers hear most weeks is some version of: 'Are Wegovy and Mounjaro the same thing?' They are not. They share a family resemblance (both are injectable medicines that work partly through the GLP-1 pathway) but semaglutide activates one receptor type, while tirzepatide activates two. That difference has clinical implications, including in how they performed in trials. If you are trying to weigh up the two, our Wegovy overview lays out what semaglutide is licensed for and how it works in practical terms.

None of this makes one medicine categorically 'better'. Which suits a given person is a clinical question, not a brand loyalty one.

What semaglutide actually is and who makes it

Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist. It mimics a gut hormone that the body releases after eating, slowing how quickly the stomach empties, increasing feelings of fullness, and reducing appetite. Novo Nordisk developed it and holds the licences for both of its UK-approved brand names.

Wegovy (semaglutide 2.4 mg, once-weekly injection) is licensed in the UK for weight management in adults with a BMI of 30 or above, or 27 to 29.9 with at least one weight-related condition. It is a Black Triangle medicine, meaning the MHRA keeps it under additional monitoring. The STEP 1 clinical trial reported an average body-weight reduction of around 15% over 68 weeks at the semaglutide 2.4 mg maintenance dose, as published in the New England Journal of Medicine.

Ozempic is also semaglutide, but it carries a different licence: type 2 diabetes management, not weight loss. The NHS is clear on this distinction, and prescribing Ozempic for weight loss is outside its licensed indication. If weight management is your goal, Wegovy is the relevant product.

In June 2026, the MHRA also approved an oral formulation: Wegovy tablets (semaglutide with an absorption enhancer), making it the first oral GLP-1 medicine licensed for weight management in the UK. You can read more about how the tablet compares to the injection on our semaglutide information page.

What Eli Lilly actually makes, and how tirzepatide differs

Eli Lilly's contribution to this field is tirzepatide, marketed in the UK as Mounjaro. Where semaglutide targets a single receptor (GLP-1), tirzepatide activates both the GLP-1 receptor and the GIP (glucose-dependent insulinotropic polypeptide) receptor. This dual action is why tirzepatide is sometimes described as working through two pathways rather than one.

In the SURMOUNT-1 trial, tirzepatide at its highest dose produced average weight reductions of around 20 to 21% over 72 weeks. The SURMOUNT-5 head-to-head trial, published in the New England Journal of Medicine in 2025, found tirzepatide produced greater average weight loss than semaglutide 2.4 mg, though NICE notes in its appraisal of tirzepatide (NICE TA1026) that indirect comparisons should be interpreted carefully.

Neither result tells you which medicine is right for you personally. Tolerability, your medical history, any medicines you already take, and clinical suitability all factor into that decision. If you want to understand semaglutide's dose schedule or how it sits alongside other treatments, a prescriber is the right person to ask.

Tirzepatide is also a prescription-only medicine, subject to the same requirement for clinical assessment before it can be prescribed.

Getting semaglutide through a regulated UK pharmacy

Both Wegovy and Mounjaro are prescription-only medicines (POMs) under UK law. That means neither can be legally supplied without a prescription following a clinical assessment, regardless of which company made them or how they are marketed. This is worth stating plainly because counterfeit and unlicensed versions of weight-loss injectables do circulate online, and the MHRA has warned repeatedly about the risks of purchasing these medicines from unverified sources.

The safe route is straightforward: a registered online pharmacy, verifiable on the GPhC pharmacy register, with a licensed prescriber reviewing your information before anything is dispensed.

At nume, every consultation is reviewed by a GPhC-registered Independent Prescriber, a real clinician reads your answers, not an automated system. Treatment is dispatched the same day if approved before 12pm, and delivered the next working day by DPD in plain packaging. Our weight-loss treatments page covers what is included and how the process works.

If you are exploring your options more broadly, our weight management overview and the about us page give a fuller picture of how we work. Questions about the relationship between Lilly and semaglutide or anything else for our team can go through our contact page at any time. If you would like detail on how the semaglutide 3 mg starting dose fits into the treatment journey, that page covers the early weeks of the dose escalation schedule.