How Long Will 10mg of Semaglutide Last — and What Affects It?

What the pharmacokinetic evidence tells us about a weekly dose

The STEP 1 trial, published in the New England Journal of Medicine and the basis for the 2.4mg maintenance dose that NICE later recommended, built its conclusions on semaglutide's well-characterised pharmacology. Because the molecule binds strongly to albumin in the blood, it is cleared slowly, the elimination half-life sits at roughly seven days. That means each injection does not fully leave your system before the next one arrives; instead, plasma concentrations rise steadily over four to five weeks until they reach a stable plateau. At that plateau, each weekly dose sustains the level rather than producing a sharp peak and trough.

In practical terms, a single dose at any strength remains pharmacologically active for the full seven-day dosing interval, and residual drug persists for several weeks after the last injection. A dedicated page on how long semaglutide stays in the system after stopping covers that tail-off in more detail. The point here is that duration is not simply a function of dose size, it is built into the molecule's chemistry regardless of the milligram figure on the pen.

Why 10mg does not appear in the Wegovy dosing schedule

The licensed Wegovy injection titration steps, as set out in the Summary of Product Characteristics on the electronic Medicines Compendium, are 0.25mg, 0.5mg, 1.0mg, 1.7mg and 2.4mg, with 7.2mg available following the MHRA's approval of the higher-dose pen in April 2026. There is no 10mg step. If you are researching this figure, you may have encountered content about compounded or unlicensed preparations sold outside the regulated supply chain, a category the MHRA has repeatedly warned about.

It is also worth knowing that Rybelsus, the oral semaglutide tablet licensed for type 2 diabetes, comes in 3mg, 7mg and 14mg strengths. Wegovy tablets, approved for weight management in June 2026, use a completely separate schedule of 1.5mg → 4mg → 9mg → 25mg. Neither matches a 10mg figure. If you want to understand what the licensed doses actually look like, the full Wegovy dose breakdown sets it out clearly. A quick check of the licensed strengths listed there takes under a minute and will tell you whether a dose you have been quoted falls within the approved range.

Supply and duration: how long does a course at a specific strength last?

For licensed Wegovy injection pens, each pre-filled pen is designed for a set number of weekly doses at the prescribed strength. Duration of supply therefore depends on which dose you are on and how many pens are dispensed in a single order. Someone beginning titration at 0.25mg and moving through 0.5mg and 1.0mg spends approximately four weeks at each level before the prescriber reviews progress; someone at the 2.4mg maintenance dose receives enough medication to cover the agreed interval between clinical reviews.

The per-dose duration question and the 5mg semaglutide duration page explore these mechanics at specific prescription strengths. What they share is the same underlying answer: one pen, one strength, one dose per week, the prescriber decides both the strength and the interval. For context on how this fits within the wider cost picture of private treatment, the weight-loss treatment overview explains what a private prescription service includes.

The NHS medicines information page for semaglutide confirms the weekly schedule and lists the information a patient should have before starting, including the importance of not adjusting doses independently. That principle applies equally to duration decisions: running a pen longer than prescribed, splitting doses, or switching between strengths without clinical guidance undermines both safety and the titration logic the prescriber has built for you.

What a prescriber actually considers when setting dose and duration

A prescriber reviewing a semaglutide consultation looks at the clinical picture as a whole: current weight, comorbidities, any medicines that may interact, tolerance of previous GLP-1 treatment and (where someone is transferring from another provider) evidence of what they have already been taking. Dose increases are not automatic; they follow a clinical assessment, not a calendar. At nume, every repeat order is reviewed before dispatch rather than issued on a rolling subscription, which means the duration of each supply is tied to that review cycle rather than to an arbitrary period.

If you have seen a 10mg preparation described as a weight-loss treatment, the safest step is to bring it to a conversation with a prescriber before using anything, and if you are working with a compounded product our guide on how to mix 10mg semaglutide explains the preparation process in detail. Our prescribers are GPhC-registered and review consultations on the same day they arrive. You can read more about the clinical team's approach on the clinical team profile if that helps you decide whether to take the next step.