Semaglutide Options for Weight Loss: What the Evidence Says

What the clinical trials actually found for each format

The Wegovy injection's headline evidence comes from the STEP programme. In STEP 1, published in the New England Journal of Medicine, adults with obesity using the 2.4mg weekly dose lost roughly 15% of body weight on average over 68 weeks, alongside lifestyle support. That figure comes from a large placebo-controlled trial and is the number NICE used when evaluating the medicine.

The higher 7.2mg dose has since received MHRA approval. A dedicated single-dose pen was authorised on 14 April 2026 for adults with a BMI of 30 or above, and trials at this dose reported average weight loss of around 20.7% over 72 weeks — closer to the results seen with tirzepatide at its highest dose. You can read more about how semaglutide works mechanically on our page covering the mechanism in detail.

For the tablet, the OASIS 4 trial (307 adults, 64 weeks, without diabetes) found an average weight loss of roughly 13.6% against around 2.4% for placebo. Among participants who stayed fully adherent throughout the trial, the figure was closer to 16.6%. That distinction matters: the 13.6% is the population average regardless of adherence, and it is the more honest starting point when thinking about what to expect. The most common side effects in the tablet trial were gastrointestinal, affecting around 74% of participants, compared with 42% on placebo, though most were described as mild to moderate and tended to settle over time.

How the injection and tablet differ in practice

The injection is once weekly, delivered via a pre-filled pen into the abdomen, thigh or upper arm. It needs to be stored in the fridge. The tablet is once daily, first thing in the morning, on an empty stomach with a small amount of plain water, with a wait of at least 30 minutes before any food, drink or other medicines. No fridge needed, which many people find useful for travel or for fitting around work.

Titration applies to both. The injection starts at 0.25mg and increases roughly every four weeks under prescriber guidance, with 2.4mg as the standard maintenance dose and 7.2mg as the current maximum. The tablet starts at 1.5mg and steps up through 4mg and 9mg to a 25mg maintenance dose, again with a minimum of one month at each level. Specific timing and changes are always directed by your prescriber and the patient information leaflet, not a general guide like this one.

If you are already on the 2.4mg weekly injection and a prescriber considers moving you to the tablet, clinical evidence supports going directly to the 25mg tablet dose rather than re-titrating from the bottom, though that decision rests entirely with the clinician. Our overview of how semaglutide is used for weight loss covers both formats in a practical context.

Who these options are licensed for — and when NHS access applies

Both formats share broadly similar licensed eligibility: adults with a BMI of 30 or above, or 27 or above with at least one weight-related condition such as high blood pressure, type 2 diabetes or obstructive sleep apnoea. Lower thresholds apply for some ethnic backgrounds under UK guidance. A prescriber looks at the full picture, not BMI alone.

NHS access for semaglutide injection (Wegovy) is available only through specialist weight management services under NICE's technology appraisal TA875, which limits it to a maximum of two years and requires multidisciplinary support. Waiting lists are commonly long. The Wegovy tablet, approved by the MHRA in June 2026, had not gone through a NICE appraisal at the time of writing and is not available on the NHS. If NHS timelines are a concern, it is worth understanding the private route clearly before deciding.

For context on what private treatment costs and what is included in a transparent service, our Wegovy cost page sets out the market picture honestly. And if you are still deciding which type of semaglutide product fits your situation, our semaglutide options overview covers the broader landscape, including the distinction between weight-loss and diabetes-licensed products.

A note on ozempic, rybelsus and unlicensed semaglutide products

It is worth being direct about something people searching this topic often find confusing. Ozempic is also semaglutide, but it is licensed for type 2 diabetes, not weight management. Rybelsus is also oral semaglutide, again for diabetes, at doses of 3mg, 7mg and 14mg, these are not the same as the Wegovy tablet schedule and should not be used interchangeably. If you have come across what looks like a cheaper version of either product being offered online, the MHRA's Yellow Card scheme exists specifically to report suspect sellers, and the MHRA has seized large quantities of fake weight-loss pens sold without proper prescription processes.

If you want a clearer picture of what the evidence says about semaglutide for weight loss, including how the results compare across different patient groups, our dedicated page brings that together in one place. Semaglutide for weight loss, whether injection or tablet, is a prescription-only medicine. The only legal route in the UK is through a registered prescriber following clinical assessment. At nume, a GPhC-registered Independent Prescriber reviews every consultation the same day. If you would like to understand your options properly, you can read more about whether semaglutide can be used for weight loss or explore our full treatment range. If you have a specific question our prescribers can help with, the contact page is always open. When you are ready, check your eligibility with a free consultation, there's no obligation, and the review is clinical, not automated.