How Much Weight Can You Lose on Semaglutide — and What Shapes That Number?

The myth worth clearing up: a bigger number on the box doesn't mean a bigger number on the scale

A lot of people arrive at the question of semaglutide results having already decided that the highest dose must produce the best outcome for them personally. That's understandable, and it's also where the thinking can go sideways. Trial averages are exactly that, averages drawn from thousands of participants. The STEP 1 trial, published in the New England Journal of Medicine, reported roughly 15% average body-weight reduction over 68 weeks at the 2.4mg maintenance dose, alongside diet and activity changes. Some participants lost considerably more; others less. Genetics, baseline weight, how consistently treatment runs, and what happens alongside the pen all feed into where any individual lands. A prescriber who knows your full picture is far better placed to set realistic expectations than a headline percentage. That doesn't mean the data is unimpressive, 15% average over 68 weeks, in a well-controlled trial, is a substantial clinical result. It just means the number is a range, not a promise, and it's worth holding it that way.

How much can you lose on semaglutide in a month, and what drives month-to-month variation?

Early in treatment, when doses are low for tolerability reasons, weight change tends to be modest. The titration schedule works up gradually, and the months on the maintenance dose tend to show the greatest effect. So asking how much you lose on semaglutide in a month produces a different answer depending on which month you mean. Across the full 68-week STEP 1 period, the average monthly rate of loss was roughly 0.9–1.0 kg, but that flattens out a ramp that starts gently and steepens as the dose increases. People who stay on treatment longer, maintain the lifestyle changes their prescriber recommended, and keep their clinical support in place tend to do better. Those who stop early because of side effects, or who treat the injection as a standalone fix, tend to see results tail off. The clinical support element is not a soft add-on. It's part of the mechanism.

For a fuller breakdown of what individual factors affect total loss when taking semaglutide, this page explores the variables in more detail.

What private semaglutide costs in the UK, and what the headline price often leaves out

UK private treatment prices for semaglutide vary between providers and by dose. Since Novo Nordisk's pricing moves and broader market changes through 2025, typical private prices have ranged from roughly £149 to over £300 per month depending on dose and provider, these figures are widely reported and should be treated as indicative rather than fixed. A detailed breakdown of Wegovy pricing in the UK covers how those ranges work in practice.

What headline prices often omit: some providers charge separately for the initial consultation, the prescription itself, and delivery. Aftercare (the ongoing clinical support that actually influences your results) is sometimes absent entirely, or gated behind an additional fee. That matters because semaglutide is not a medicine you titrate and manage without clinical input; it's a prescription-only treatment requiring regular review. When comparing costs, the fair comparison is total cost of a supervised month, not the lowest listed pen price. See how to read a semaglutide quote honestly before committing to any provider.

Why the cheapest route is often the most expensive one

For a prescription medicine, price is the wrong test. The MHRA has warned repeatedly about counterfeit weight-loss pens sold online and via social media, fake pens seized in the UK have contained insulin instead of semaglutide, and enforcement operations through 2025 removed around 20 million doses of illegally traded weight-loss medicines worth approximately £45m from the supply chain. A low price from an unverified seller is a red flag, not a bargain. You can verify any online pharmacy on the GPhC register, it takes thirty seconds and tells you immediately whether a pharmacy is regulated.

At nume, we are not the cheapest option. That's a deliberate choice. One price covers consultation, prescription, treatment, and free next-working-day DPD delivery in plain packaging. There are no hidden fees. You can explore what's included on our treatment page, and our about us page explains the clinical infrastructure behind the service. If you have questions before starting, our FAQs cover the most common ones, and our team is available seven days a week.

A small saving on a pen that arrives from an unverified source, with no prescriber review and no aftercare, answers the wrong question entirely. The right question is whether the care behind the medicine is good enough to produce the results you're looking for. Check your eligibility and start your free consultation with a prescriber who can give you a straight answer about what to expect.