The Semaglutide Starting Dose for Weight Loss, Explained

What the licensed schedule actually looks like

The Wegovy prescribing information, as published on the electronic Medicines Compendium, sets out a fixed titration ladder: 0.25 mg weekly for four weeks, then 0.5 mg, 1.0 mg, 1.7 mg, each held for roughly four weeks, before reaching the 2.4 mg maintenance dose. The full Wegovy dose schedule runs to around 16–20 weeks before a patient reaches that maintenance level. More recently, the MHRA approved a 7.2 mg maximum dose (initially supplied as three 2.4 mg pens weekly, and from April 2026 as a dedicated single-dose pen) for adults with a BMI of 30 or above, titrated by the prescriber in the same stepwise fashion.

The word "starting" matters here. At 0.25 mg, semaglutide is present in the body at a low enough concentration that the gastrointestinal effects common at higher doses (nausea in particular) are usually mild. The NHS medicines information for semaglutide confirms that most GI side effects peak early and settle as the body adapts. Rushing the schedule to reach a higher dose faster is a clinical decision, not a patient one.

The starting dose of Wegovy for weight loss is therefore a platform, not a target. Weight loss at this stage is modest. That is expected, and it is built into the trial design: the relationship between semaglutide dose and weight loss outcomes becomes clinically meaningful at higher maintenance doses.

What the trial evidence shows about dose and outcomes

The STEP 1 trial, published in the New England Journal of Medicine, randomised 1,961 adults with obesity or overweight and at least one weight-related condition to semaglutide 2.4 mg or placebo over 68 weeks, alongside lifestyle intervention. Average weight reduction in the semaglutide group was around 15% of body weight. That figure is specific to the 2.4 mg maintenance dose, participants spent the first several months titrating up through the same ladder described above.

The newer 7.2 mg dose has produced trial data suggesting approximately 20.7% average weight loss over 72 weeks, approaching the results seen with tirzepatide at its highest licensed dose. NICE's appraisal of semaglutide (Wegovy), published as TA875, focuses on the 2.4 mg dose and recommends considering stopping treatment if less than 5% weight loss has occurred after six months at the maintenance dose. That threshold exists precisely because the starting dose contributes little to the outcome figure, the evidence base is built on what happens at steady state.

For anyone considering a dose close to the 2.4 mg maintenance level, it is worth understanding that the titration period is not wasted time. Each step reduces the chance that side effects become severe enough to interrupt treatment altogether.

Who the licensed starting dose applies to

In the UK, Wegovy (semaglutide injection for weight loss) is licensed for 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, raised cholesterol, type 2 diabetes or obstructive sleep apnoea. Lower BMI thresholds can apply for some ethnic backgrounds under UK guidance. If you are unsure where you fit in the titration ladder, our guide covering what the starting dose for semaglutide means in practice explains eligibility and dose selection in plain terms.

Semaglutide is not licensed for weight loss in people under 18, during pregnancy or breastfeeding, or for those who are trying to conceive. A history of certain conditions, including pancreatitis, requires prescriber discussion before treatment starts. BMI alone does not determine suitability, a prescriber considers the full clinical picture, including medical history and current medicines.

On the NHS, Wegovy is available through specialist weight management services under NICE TA875, with significant waiting times in most areas. For a broader look at private and NHS routes, the weight loss treatment options page sets out what is available. Privately, the route is a clinical consultation: a GPhC-registered prescriber reviews your details, and treatment is only supplied where it is clinically appropriate. Our clinical team is introduced on the clinical lead profile page.

Side effects to expect during the titration period

The most commonly reported side effects of semaglutide are gastrointestinal, nausea, loose stools, constipation, indigestion, reflux and burping. These are most noticeable in the first few days after a new dose and often settle within one to two weeks. The NHS medicines page for semaglutide lists these in detail alongside the less common effects to watch for.

There are symptoms that warrant prompt medical attention regardless of where someone is in the titration schedule: severe, persistent stomach pain that spreads to the back (which may indicate pancreatitis), signs of a serious allergic reaction, or any symptoms of significant dehydration from repeated vomiting or diarrhoea. The MHRA has a Yellow Card scheme at yellowcard.mhra.gov.uk where patients and carers can report suspected side effects.

A question the prescribers at nume hear regularly: can the titration be slowed down? Yes. If side effects are difficult at a given dose, the prescriber may recommend staying at that level for longer before the next increase. For patients who have moved through the earlier steps and are tolerating treatment well, our page on what to expect at the semaglutide 1mg stage covers how that dose fits into the wider schedule. Some people reach 2.4 mg in 16 weeks; others take longer, and our page on the semaglutide starting dose explains why the initial weeks are designed the way they are. Slowing down is not failure, it is the schedule working as intended. If you have questions between appointments, our support team is available seven days a week.