Mixing 5mg Semaglutide: What Patients Are Actually Asking

You've found a vial and a mixing chart, here's the context you need

Picture this: you've been given a small glass vial labelled "semaglutide 5mg" alongside a separate diluent, a syringe and a chart explaining how many units to draw up for each weekly dose. This setup is common in countries where compounded semaglutide is legally prepared by pharmacies, and it has migrated into UK social media and online marketplaces. The chart typically breaks one vial across multiple weeks, with users drawing up fractions of a millilitre depending on their target dose.

In the UK, compounded semaglutide is not a licensed medicine. The MHRA has specifically warned the public about unlicensed preparations (including vials requiring home mixing) sold through social media and unregistered websites. Reconstituting a lyophilised powder carries risks that a pre-filled pen eliminates: incorrect concentration, contamination during preparation, improper storage after reconstitution, and no standardised sterility guarantee. A semaglutide mixing chart for 5mg may look straightforward, but it places the accuracy of your dose in your own hands without the quality controls a licensed manufacturer applies, and those preparing larger volumes can find a similar set of concerns explored in the semaglutide mixing chart for 10mg vials.

If you want to understand the licensed Wegovy dose progression, the full Wegovy dose schedule explains what each step looks like and why the titration exists.

The 5mg figure does not appear in the Wegovy maintenance schedule

This is the detail that trips people up. The licensed Wegovy injection pathway runs from 0.25mg through to a maintenance dose of 2.4mg weekly, with the newer 7.2mg option now MHRA-approved for adults with a BMI of 30 or above. A 5mg weekly dose does not exist anywhere in that schedule. If you're reading a mixing chart that refers to 5mg of semaglutide per vial as a starting point, it is describing a compounded product designed to be diluted and subdivided, not a step in the licensed treatment programme.

Wegovy's licensed maintenance route matters because it was the basis for the clinical evidence. The STEP 1 trial, published in the New England Journal of Medicine, followed adults on semaglutide 2.4mg weekly for 68 weeks and reported an average body-weight reduction of around 15%. That evidence underpins the UK licence and the NICE recommendation. Compounded preparations were not part of that trial programme and carry no equivalent evidence base in the UK context.

For a closer look at how individual licensed doses compare, the page on semaglutide dosing covers the rationale behind each step in plain terms.

Storage, routine and why it matters which product you hold

One of the clearest practical differences between a licensed pen and a compounded vial is what you do with it once it arrives. A Wegovy KwikPen lives in the fridge door between uses, ready to go at the same time each week, and never needs anything added to it. A reconstituted vial, once mixed, typically needs refrigeration within minutes and must be used within a defined window, but that window varies depending on the diluent used and the concentration prepared, and there is no standardised UK-licensed guidance covering it. The NHS semaglutide patient information covers storage and handling for the licensed product; it does not extend to compounded versions.

If you are currently using a vial-based preparation and have questions about whether to continue, that conversation belongs with a prescriber, not a mixing chart. The semaglutide mixing and dosage overview gives broader context on why these questions arise and what the licensed framework looks like.

What to do if you have been prescribed compounded semaglutide

Some patients arrive at services like ours having already started on a compounded product from another provider, sometimes abroad. The right step is a clinical conversation, not an immediate switch or an abrupt stop. A GPhC-registered prescriber needs to know your current preparation, dose and how long you have been taking it before making any recommendation.

Licensed semaglutide (Wegovy) is available in the UK through regulated private pharmacies following a prescription assessment. The Wegovy treatment overview explains who the medicine is licensed for and what the assessment covers. For context on private treatment costs, the Wegovy price comparison guide covers what a legitimate prescription service typically includes. If anything about your current situation feels uncertain, our support team is reachable seven days a week and can point you to the right clinical pathway. At the end of that pathway is a free consultation, reviewed by a real prescriber, not software, and that is where the right dose decision gets made.