Semaglutide weight loss per month: what the trial data actually shows

What the STEP 1 trial tells us about monthly weight loss on semaglutide

The STEP 1 trial, published in the New England Journal of Medicine, followed 1,961 adults with obesity over 68 weeks. Average body-weight reduction at the end of the trial was around 15% on semaglutide 2.4mg versus about 2.4% on placebo. Spread across 68 weeks that works out to roughly two to three kilograms per month on average, but the curve is not linear. The earliest months, when appetite suppression tends to be most pronounced even on starter doses, often account for a disproportionate share of total loss. Later months, especially when titration has plateaued, may show slower progress.

Two things follow from this. First, a single month's result is a poor proxy for overall effectiveness, asking "how much weight loss in a month" is really asking about a snapshot rather than a trajectory. Second, monthly progress is dose-dependent. The titration schedule for Wegovy moves from 0.25 mg up through 0.5 mg, 1.0 mg and 1.7 mg before reaching the 2.4 mg maintenance dose, with roughly four weeks at each level, and understanding how much semaglutide to take for weight loss helps explain why results at each stage can vary so considerably. Someone three months in is still climbing that ladder. The week-by-week picture can look quite different again.

NICE recommends considering stopping treatment if less than 5% weight loss is achieved after six months on the maintenance dose, which implies that modest early results should be interpreted alongside clinical context, not in isolation. Your prescriber is the right person to read those numbers with you.

How private semaglutide pricing actually works in the UK

Private weight-loss treatment in the UK is priced per pen per month, and what you pay depends on the dose and the provider. Since Eli Lilly raised Mounjaro's list price from September 2025, the wider GLP-1 market has shifted; semaglutide pricing has followed its own trajectory. Across the private market, monthly costs for Wegovy typically fall somewhere in a broad range, the exact figure varies by dose, provider and what the price actually includes. If a headline price looks low, it is worth asking what it covers.

Many advertised prices exclude the consultation fee, the prescription charge, delivery, and ongoing clinical support. You could start with an attractive per-pen figure and find the real monthly outlay is materially higher once those are added. A fuller breakdown of semaglutide pricing in the UK is worth reading before you commit anywhere.

At nume, one price covers everything: the consultation, the prescription, the medicine, free next-working-day delivery via DPD, and seven-day aftercare. No bolt-ons. We are not the cheapest option on the market, and that is a deliberate choice, the margin funds the clinical infrastructure (same-day prescriber review, live weight verification, GP notification, clinical re-review before every repeat) rather than a race to the lowest listing. Current treatment pricing is on our treatment page.

What monthly progress actually costs you to sustain

If average monthly weight loss is dose-dependent, and you spend three or four months on sub-therapeutic starter doses before reaching 2.4 mg, then the cost per kilogram lost in those early months is highest. That is not an argument against the titration schedule (it exists to reduce gastrointestinal side effects and is clinically sensible) but it is an argument for choosing a provider where clinical oversight across the full titration journey is included in what you pay.

Providers who charge separately for each follow-up or dose-increase review create a financial disincentive to seek the support that makes titration go well. At nume, there are no separate charges for repeat clinical reviews. If you want to understand what a full course might look like financially before starting, the Wegovy pricing page sets out the context clearly. For a sense of how monthly results compare across the titration period, month-one Wegovy expectations is a good starting point.

One practical note: if you order by 12pm on a weekday, once your consultation is clinically approved your treatment dispatches the same day. That matters if you are mid-titration and running low, a gap in treatment can affect progress.

Why price is the wrong first question for a prescription medicine

Semaglutide is a prescription-only medicine. The legal route to it in the UK is a prescription issued after a clinical assessment by a qualified prescriber. Sellers who offer GLP-1 medicines without that step are operating outside UK law. The MHRA has warned repeatedly about counterfeit weight-loss pens sold online, some have contained insulin rather than semaglutide, with serious consequences for buyers. You can verify any online pharmacy at the GPhC register; nume's premises registration number is 9012878.

Discount codes for prescription medicines from unverified sellers are a red flag, not a saving. Prices well below the private market rate should prompt the same question. The guide to where people look for cheaper Wegovy covers what those searches tend to turn up and what to watch for. For the clinical picture (how semaglutide works, who it suits, and what the evidence says about results) the Wegovy overview is the place to start. And if you are ready to see whether treatment is clinically suitable for you, our prescribers are available seven days a week.