Is Semaglutide a GLP-1 Drug, and What Does That Actually Mean?

Step 1: understanding what GLP-1 actually is

GLP-1 stands for glucagon-like peptide-1. Your intestine secretes it within minutes of eating, and it does several things at once: it tells your pancreas to release insulin in proportion to blood glucose, it suppresses glucagon (the hormone that raises blood sugar), it slows gastric emptying so food moves through you more gradually, and it signals to appetite centres in the brain that you have eaten enough. Under normal circumstances, the hormone is broken down by an enzyme called DPP-4 within two or three minutes of release, which limits how long these effects last.

Semaglutide is a lab-engineered analogue of that hormone. Researchers modified the natural GLP-1 molecule so that DPP-4 can no longer break it down quickly, and attached it to a fatty-acid chain that binds to albumin in the bloodstream. The result is a molecule that behaves like GLP-1 but persists for roughly a week, which is why a single weekly injection or daily tablet is sufficient. If you want a closer look at what the drug semaglutide is and how it was developed, our dedicated page goes into the science in more depth. You can read more about the broader category of GLP-1 medicines on our semaglutide and GLP-1 overview page.

The NHS describes semaglutide's primary mechanism as reducing appetite and slowing gastric emptying, and its patient information reflects exactly these effects. The NHS medicines page for semaglutide is a reliable first stop for plain-language information on how the drug works and what to expect.

Step 2: how semaglutide differs from other GLP-1 drugs

Not all GLP-1 receptor agonists are the same molecule. Liraglutide (Saxenda and Victoza), exenatide, dulaglutide and others all act on the GLP-1 receptor, but they differ in their molecular structure, dosing frequency, delivery method, and clinical evidence base. Semaglutide is the only GLP-1 drug currently available in both injectable and oral forms for weight management in the UK.

Tirzepatide, sold as Mounjaro, works differently: it is a dual GIP and GLP-1 receptor agonist, activating two separate gut-hormone pathways. That distinction matters clinically and is reflected in the trial evidence. Head-to-head data from the SURMOUNT-5 trial published in the New England Journal of Medicine (2025) showed tirzepatide produced greater average weight loss than semaglutide 2.4mg over 72 weeks. Whether the difference matters for a specific person is a clinical question, not a marketing one. If you want to explore the differences between these two options, our semaglutide treatment guide covers the comparison in detail.

Within semaglutide itself, the dose defines the indication. The 2.4mg weekly injection and the 25mg daily tablet are licensed for weight management under the Wegovy brand. The 0.5mg and 1mg doses under the Ozempic brand are licensed for type 2 diabetes. Using Ozempic for weight loss is off-label and, in the UK, not appropriate, something the MHRA has been explicit about.

Step 3: the forms semaglutide takes in the UK today

Until recently, semaglutide for weight management meant a once-weekly subcutaneous injection. The pen is pre-filled, and treatment starts at a low dose to let the body adjust before titration upward. The MHRA then approved a higher 7.2mg maintenance dose in January 2026, with a dedicated single-dose pen following in April 2026, offering adults with obesity a stronger option within the same injection format.

Then, on 11 June 2026, the MHRA approved Wegovy tablets, making the UK the first country in Europe to license an oral GLP-1 medicine for weight management. The tablet schedule runs from 1.5mg daily up to a 25mg maintenance dose, taken first thing in the morning on an empty stomach with a small amount of plain water, at least 30 minutes before food or other medicines. No refrigeration is needed, which many people find convenient for travel or daily routine. Our page on the forms semaglutide comes in covers both the injection and tablet schedules in detail, including what the titration process involves. Is Wegovy a GLP-1 drug? Yes, in both its injection and tablet forms, the receptor mechanism is the same; what changes is how the molecule reaches your bloodstream.

Both forms remain prescription-only medicines. A prescriber decides the appropriate formulation and starting point based on your clinical picture, not on patient preference alone. For current pricing context on private treatment in the UK, our Wegovy price comparison page sets out what the private market looks like and what a legitimate prescription service should include.

Step 4: what GLP-1 drug status means for how you access it

Because semaglutide is a prescription-only medicine, the GLP-1 mechanism alone does not determine access, eligibility criteria and clinical assessment do. Under its NICE appraisal (TA875), Wegovy on the NHS is available through specialist weight management services for adults meeting specific BMI and comorbidity thresholds, for a maximum of two years. NHS waiting lists are often long, and the criteria are strict.

Private prescribing is the route most people take outside NHS pathways. At nume, every consultation is reviewed the same day by a GPhC-registered Independent Prescriber, a real clinician reading your answers, not a decision tree. If approved, treatment is dispatched the same day for free next-working-day DPD delivery; the plain, unbranded box that arrives the following morning contains the pen or tablets your prescriber has selected, with tracking sent to your phone. To understand the full range of weight-loss treatments available and find out whether semaglutide is suitable for you, visit our weight-loss treatment overview.

A question our prescribers hear regularly is whether a person's GP can prescribe Wegovy directly. From April 2026, some GP practices can prescribe tirzepatide under the updated NHS contract, semaglutide via Wegovy remains within specialist services for NHS purposes, though a private GP or online prescriber can assess and prescribe it. The Wegovy treatment page explains the private route and what eligibility looks like in practice.