Semaglutide Fact Sheet: The Key Facts at a Glance

Step 1: understanding what semaglutide is and how it acts in the body

Semaglutide belongs to a class of medicines called GLP-1 receptor agonists. GLP-1 is a hormone your gut releases after a meal; it tells the brain you have eaten, slows the rate at which the stomach empties and nudges the pancreas to release insulin when blood sugar is raised. Semaglutide mimics this effect continuously, which is why people taking it typically feel full sooner and eat less over time. If you want a thorough grounding before your consultation, the semaglutide facts page covers the key science behind how the medicine works. That reduction in appetite is not a side effect, it is the mechanism.

The NHS medicines page for semaglutide explains this pathway clearly, and it is worth reading before any consultation. What it will not tell you is how your body will respond individually, that depends on your health history, other medicines and the dose your prescriber chooses. The drug acts on receptors in both the gut and the brain, which is why the fullness signal feels different from simply eating a large meal.

One practical detail: semaglutide's half-life is about a week, which is why a once-weekly injection is enough to maintain a steady concentration. Missing a dose by a day rarely matters; missing one entirely or taking it twice is something to discuss with your prescriber, not to judge from a forum.

Step 2: the licensed strengths, the titration schedule and the 7.2 mg pen

The UK weight-management injection follows a gradual titration: 0.25 mg for four weeks, then 0.5 mg, 1.0 mg, 1.7 mg and finally 2.4 mg, each step held for roughly a month. The slow ramp is deliberate, it gives the digestive system time to adjust and reduces the intensity of early nausea. Jumping straight to a higher dose would not produce faster results; it would produce more side effects.

In January 2026 the MHRA approved a 7.2 mg maintenance dose, initially delivered as three 2.4 mg pens per week. On 14 April 2026 a dedicated single-dose 7.2 mg pen received MHRA approval, one pre-set weekly injection with an auto-dosing mechanism and a built-in covered needle. This higher dose is licensed for adults with a BMI of 30 or above; the starting dose and titration path remain the same. Trials reported around 20.7% average weight loss at 7.2 mg over 72 weeks, which narrows the gap with tirzepatide 15 mg results.

If you are considering your options across the two licensed weight-loss injections, the Wegovy overview page sets out the UK-specific detail. Specific pen availability and which dose is appropriate for you are confirmed at the consultation stage, not before.

Step 3: what the clinical evidence says, and what it does not

The STEP 1 trial, published in the New England Journal of Medicine, followed 1,961 adults with obesity or overweight and at least one weight-related condition for 68 weeks. Participants taking semaglutide 2.4 mg lost an average of around 15% of their body weight compared with around 2.4% for placebo, and that was alongside lifestyle changes for both groups. Around a third of participants lost more than 20%.

Those figures are averages from a clinical trial, not a promise. Response varies, and the medicine works alongside a reduced-calorie diet and increased activity, not instead of them. NICE's appraisal of semaglutide (TA875) accepted the evidence as sufficient to recommend NHS use, but only within specialist weight management services, for a maximum of two years, and with multidisciplinary support. If fewer than 5% of body weight is lost after six months on the maintenance dose, continuing is reviewed. That ceiling and those conditions matter for anyone comparing NHS and private routes.

For anyone curious about what happens when treatment stops, the evidence on weight regain after Wegovy is addressed separately, it is a common and legitimate question our prescribers hear regularly, and the trial data there is worth understanding before starting.

Step 4: eligibility, side effects and the prescription process

The licensed eligibility for semaglutide (Wegovy) in a private setting is adults with a BMI of 30 or above, or 27 to 29.9 with at least one weight-related condition such as high blood pressure, type 2 diabetes, high cholesterol or obstructive sleep apnoea. Lower thresholds apply for some ethnic backgrounds under UK guidance. BMI is a starting point, not an automatic pass, the prescriber reviews the full picture, including other medicines and medical history.

Side effects are predominantly gastrointestinal: nausea, loose stools, constipation, indigestion and, less commonly, vomiting. These are most noticeable in the first few weeks or after a dose increase, and they usually settle. Severe, persistent stomach pain that radiates to the back is a reason to seek urgent medical attention, given what is known about pancreatitis as an infrequent but serious risk with GLP-1 medicines. The MHRA highlighted this in a Drug Safety Update issued in January 2026.

At nume, a real clinician reads your consultation answers and makes the prescribing decision the same day, no automated triage, no queuing system. If approved before noon on a working day, your treatment is dispatched that day and arrives via tracked DPD delivery the following morning. For a fuller look at the Wegovy data or to explore how weight-loss treatment options compare more broadly, those pages are a good next step. Questions about our clinical team's approach are answered on the clinical team profile.

Semaglutide is a prescription-only medicine. The right place to find out whether it is suitable for you is a clinical consultation, not a fact sheet. If you are ready to take that step, speak to our prescribers, the consultation is free, and there is no obligation to proceed.