How many doses are in a semaglutide pen — and what that means for your treatment

Step 1: Understanding the four-dose structure before you start

Open any Wegovy pen and you will find it pre-loaded with four equal injections. Press the button once a week, on the same day each week, and the pen is finished after the fourth dose. There is no adjusting the dial, no splitting doses, and no leftover medicine, the device is single-strength by design.

A quick practical check you can do in under a minute: look at the label on the pen box before you inject. The strength printed there is the dose you are on for the whole four-week period. If the box says 0.25 mg, all four injections are 0.25 mg. If it says 1.7 mg, all four are 1.7 mg. Confirming this before your first injection of a new pen means you never mistake one strength for another.

This fixed-dose format is one reason the Wegovy treatment overview is worth reading before you begin, it explains how the pen fits into the broader picture of diet, activity and clinical oversight that the licence requires alongside the medicine itself.

Step 2: Moving through the titration, why each pen is a new strength

Semaglutide is introduced gradually to give your body time to adjust, particularly your digestive system. The standard pathway moves through 0.25 mg, then 0.5 mg, 1.0 mg, 1.7 mg and 2.4 mg, one pen (four weeks) at each level. The full Wegovy dose schedule sets out each stage in detail.

The 2.4 mg pen was the standard maintenance dose for several years. In January 2026 the MHRA approved a higher 7.2 mg dose, and in April 2026 a dedicated 7.2 mg single-dose pen was cleared, one pre-set injection per week, with a built-in covered needle that locks after use. For this higher dose, the pen format changed: rather than four doses in one device, the 7.2 mg pen delivers one weekly dose per pen. That is worth knowing if you or your prescriber ever discuss moving to the highest maintenance dose.

Because each step is a new prescription, your prescriber reviews your progress before issuing the next pen strength. This is not a formality, it is clinical oversight built into the structure of the treatment, and according to NHS guidance on semaglutide, titration should only happen under the direction of a healthcare professional.

Step 3: Practical implications, storage, timing and running low

Four doses per pen means four weeks of medicine. Running out earlier than expected is almost always a sign that something went wrong mechanically, a missed click, an incomplete injection or a prime-dose error when the pen was first used. If you think a dose did not deliver fully, do not give a second injection; contact your prescriber or pharmacist the same day.

Storage matters here too. Wegovy pens are refrigerated at 2–8°C until first use, after which there is a limited window at room temperature. The exact number of days is specified in the Patient Information Leaflet that comes with your pen, always refer to that rather than relying on memory, because the window differs between products.

If you are considering the cost of a month's treatment, the Wegovy cost guide explains what private pricing typically covers and what questions to ask. A legitimate prescription includes clinical review, not just the pen itself.

How dose count differs across semaglutide pen strengths

Most Wegovy strengths (0.25 mg through to 2.4 mg) follow the four-doses-per-pen rule. The 7.2 mg pen is the exception. Understanding this distinction matters if you are comparing pens or if a pharmacist discusses supply of a specific strength.

For the 0.25 mg starter pen specifically, the 0.25 mg pen dose count page covers common questions about first-pen use and what to expect. If you are looking at the 1.7 mg transition pen, the semaglutide 1.7 mg guide gives context on why that particular step exists in the titration. And for the 5 mg comparison (a question that sometimes arises when patients have previously used tirzepatide) this page on the 5 mg semaglutide pen clarifies the distinction between products.

Semaglutide's clinical evidence base is substantial. The STEP 1 trial, published in the New England Journal of Medicine, found an average weight reduction of around 15% over 68 weeks at the 2.4 mg dose in adults with obesity. These results were achieved with structured clinical support alongside the medicine, not the pen alone. Speaking to a prescriber is the right first step if you are weighing up your options. Speak to our prescribers at nume through a free consultation and find out whether Wegovy suits your circumstances.