Wegovy 1mg weight loss: what the evidence actually shows

What the STEP 1 trial tells us about semaglutide's dose-response relationship

The STEP 1 trial randomised 1,961 adults with obesity or overweight and at least one weight-related condition to weekly semaglutide 2.4mg or placebo for 68 weeks, alongside reduced-calorie eating and increased activity. The semaglutide group lost an average of around 15% of body weight versus roughly 2.4% in the placebo group, and you can read more about what weight loss at the 2.4mg maintenance dose tends to look like once titration is complete. Crucially, those results accumulated across the whole titration period, the 1mg dose was a waypoint, not the destination.

Semaglutide acts on GLP-1 receptors involved in appetite regulation and the rate at which the stomach empties. At lower doses, those effects are present but submaximal. So weight loss on 1mg Wegovy tends to be slower than it will be once 2.4mg is established, which can feel discouraging if you're not expecting it. The NHS medicines information for semaglutide describes the titration steps and notes that the full therapeutic effect builds over time. Patience at this stage is part of the clinical plan, not a sign that the medicine isn't working.

For anyone curious about what weight loss on 1mg Wegovy typically looks like in practice, the honest answer is: variable, gradual, and still early. What matters most is tolerability and laying the groundwork for the doses ahead.

Where 1mg sits on the Wegovy titration ladder

The licensed Wegovy schedule runs: 0.25mg (four weeks) → 0.5mg (four weeks) → 1mg (four weeks) → 1.7mg (four weeks) → 2.4mg maintenance. The 0.25mg starting dose is designed as a tolerability step; by 1mg, most people have moved past the worst of early nausea. You can read about the 0.5mg step and the 1.7mg step for context on how appetite suppression tends to deepen as the dose increases.

It's also worth knowing that Wegovy now has a higher authorised maintenance option: the MHRA approved a 7.2mg single-dose pen in April 2026 for adults with a BMI of 30 or above, following trial data showing around 20.7% average weight loss over 72 weeks at that level. For the majority of people, 2.4mg remains the standard endpoint, and titration still begins at 0.25mg regardless. The full Wegovy dose guide covers all steps and what to expect at each one.

A prescriber, not the person taking it, decides whether and when to advance. If side effects at 1mg are significant, staying at this dose for longer than one month is a legitimate clinical choice. If the next step feels uncertain, the place to raise it is with your clinical team, not a forum.

Side effects to know about at 1mg, and when to get medical help

GI effects (nausea, loose stools, constipation, indigestion, and occasionally vomiting) are the most commonly reported at this stage. For most people they're mild to moderate and settle within a week or two of each dose step. Keeping the pen in the same place each week (some people find tucking it into the fridge door helps make injection day a habit) reduces the chance of forgetting, which can make a restart feel worse than a steady routine.

Seek urgent medical attention for severe, persistent abdominal pain, particularly pain that radiates towards the back, this can be a sign of pancreatitis, which the MHRA highlighted as an infrequent but serious risk in its January 2026 Drug Safety Update on GLP-1 medicines. Other signs to act on promptly include symptoms of a serious allergic reaction, significant dehydration from vomiting or diarrhoea, or gallbladder-type pain. Suspected side effects from any medicine can be reported directly to the MHRA via the Yellow Card scheme.

Wegovy is not recommended during pregnancy, while breastfeeding, or when actively trying to conceive. It isn't licensed for anyone under 18. If you take an oral contraceptive pill, discuss this with your prescriber, tirzepatide (a different medicine) carries specific guidance on this point, and it's worth confirming the position for semaglutide too.

Private access, eligibility, and what comes next

On the NHS, semaglutide for weight management is available through specialist services under NICE guidance TA875, though waiting lists are commonly long and eligibility criteria are specific. Private prescribing through a regulated online pharmacy is the alternative for people who don't meet NHS thresholds or prefer not to wait, and it's worth knowing how to verify any service you consider. The GPhC pharmacy register lets you confirm whether a pharmacy holds a valid registration before you share any health information or payment details.

The licensed eligibility criteria for private prescribing follow the SmPC: 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, or obstructive sleep apnoea). Lower BMI thresholds apply for certain ethnic backgrounds under UK guidance. BMI alone doesn't decide the outcome, a prescriber looks at the whole clinical picture, including other medicines, medical history, and what you're aiming for.

If you'd like to understand where you might sit, our free consultation is the right starting point. A GPhC-registered prescriber at our pharmacy reads every submission personally and gets back to you the same day. No algorithms, no automated triage. If you want a broader look at weight management options first, the treatment overview walks through what's currently available. Check your eligibility when you're ready, there's no obligation, and the consultation costs nothing.