Wegovy weight loss by week: what the timeline actually looks like

Weeks 1–4: the starter dose does its job quietly

Treatment begins at 0.25mg, a dose chosen to let your body adjust, not to produce rapid results. That distinction matters. The first four weeks are about tolerability: your prescriber is giving the GLP-1 pathway time to settle in before the dose climbs. For most people, weight change in this opening month is modest, sometimes a kilogram or two, sometimes less. Nausea, indigestion and loose stools are common early on; they tend to ease within one to two weeks as the body acclimates.

Some people feel discouraged at week three when the scales haven't moved much. That's worth keeping in perspective. The appetite-suppressing effect builds gradually, and the full influence of semaglutide on satiety signals becomes clearer once the dose increases. If you're starting treatment around a holiday or a particularly stressful stretch, the early weeks can feel even slower, the medicine works alongside your lifestyle, not independently of it.

The Wegovy overview at nume explains how semaglutide's mechanism underpins the longer arc of results, which helps put these early weeks into context.

Weeks 5–16: the escalation phase, where most people see meaningful change

The 0.5mg dose arrives at week five, then 1.0mg at week nine, then 1.7mg at week thirteen. Each step typically brings a more pronounced appetite reduction and, for most people, a more visible change in body weight. The STEP 1 trial data shows that meaningful average reductions were accumulating through this phase, even before participants reached the 2.4mg maintenance dose.

This is the phase where week-by-week semaglutide weight loss becomes easier to observe. Many people report a natural reduction in portion sizes and less interest in eating between meals, the medicine is doing what it's designed to do, and the results start to reflect that. For a closer look at what the six-week mark tends to look like specifically, this page covers the six-week picture in more detail.

Side effects during escalation are worth tracking. If GI symptoms are severe or persistent, your prescriber may suggest staying at the current dose longer before stepping up. That's a clinical call, not a failure, and it doesn't derail the overall trajectory. Wegovy carries a Black Triangle (▼) designation, meaning the MHRA actively monitors it for new safety information.

Weeks 17 onwards: maintenance dose and the longer curve

At 2.4mg, most people reach their highest level of appetite suppression. The NHS semaglutide medicines page notes that weight loss tends to continue for some months at the maintenance dose before levelling. The STEP 1 trial ran to 68 weeks, and average reductions were still accumulating in the final stretch, which is why the 15% figure is a 68-week number, not a 16-week one.

Plateaus are common around weeks 20–30. They don't mean the medicine has stopped working; they often reflect the body settling at a new metabolic equilibrium. Protein intake, hydration and some form of regular activity all support continued progress through this phase. Personal dietary plans are best developed alongside your prescriber or a dietitian rather than guessed at.

For people whose results at twelve weeks feel slower than expected, the twelve-week milestone page addresses what's normal and what might prompt a prescriber review. And if a week or two has passed with no movement at all, the page on a week with no loss is worth reading before drawing conclusions.

The decision the timeline helps you make

Understanding the week-by-week pattern matters most when you're deciding whether to start, whether to continue, or whether to investigate a private prescription route. The NHS route to Wegovy requires referral to a specialist weight management service under NICE guidance TA875, which can mean a lengthy wait. A private prescription from a GPhC-registered pharmacy removes that wait, subject to a clinical assessment confirming suitability.

The average per-week rate of loss through the full 68-week STEP 1 trial works out at roughly 0.15–0.2% of body weight, useful context when setting expectations, less useful as a week-one yardstick. Progress is front-loaded in some people and back-loaded in others. What the data consistently shows is that meaningful results require time at the maintenance dose, not just time on the medicine. For a detailed breakdown of what the weekly rate of change looks like across the programme, this page focuses specifically on the per-week rate.

If you're weighing up whether Wegovy is the right option for you, check your eligibility with our prescribers, the consultation is free, and a clinician reviews your answers the same day.