Switching from Liraglutide to Semaglutide: What the Dosing Change Actually Means

The Biggest Misconception: You Can't Just Carry Your Liraglutide Dose Across

The most common assumption people make when moving between these two medicines is that their current liraglutide dose maps neatly onto a corresponding semaglutide dose. It does not. Liraglutide and semaglutide are both GLP-1 receptor agonists, so they share a mechanism, but they are different molecules, measured in different units, given at different intervals, and titrated along entirely different schedules. A direct milligram-for-milligram translation is clinically meaningless.

Liraglutide for weight management (Saxenda) runs from 0.6mg daily up to 3mg daily across a five-week titration, with small daily injections. Semaglutide (Wegovy) starts at 0.25mg once weekly and escalates over roughly 16 weeks to a 2.4mg weekly maintenance dose, and a higher 7.2mg maintenance option was approved by the MHRA in early 2026. The numbers look superficially similar but represent completely different pharmacokinetic profiles. Semaglutide has a half-life of about a week; liraglutide's is closer to 13 hours. Weekly dosing is possible precisely because semaglutide stays active far longer.

The practical upshot: when switching, most prescribers will restart the titration from the beginning of the semaglutide schedule rather than attempting to match an equivalent liraglutide dose. This protects against side effects during the transition and gives the new medicine time to reach steady state. The full switching process warrants its own clinical discussion.

A Direct Look at the Two Dosing Schedules

The table below sets out the approved UK dose progression for each medicine. Numbers are drawn from the respective Summaries of Product Characteristics published on the electronic Medicines Compendium (eMC). Prescribers may adapt the pace of titration based on tolerability.

Trial figures are averages from the licensed pivotal studies and are cited by the NHS for patient information. Individual results vary. The STEP 1 trial data for semaglutide 2.4mg were published in the New England Journal of Medicine (2021); the SCALE liraglutide results appear in the same journal. Neither set of figures is a guarantee of what any individual will achieve.

What the Switch Feels Like in Practice

Moving from a daily injection to a weekly one removes a routine that may have become second nature. Some people find that anchoring a weekly injection to a fixed day and time helps, pairing it with something predictable, like the moment a gym bag gets packed or a particular weekly errand, tends to work better than relying on memory alone. The question of when in the day to take Wegovy is covered separately, but unlike liraglutide there is no requirement to take it at a specific time relative to meals.

Storage requirements are similar: both medicines should be kept refrigerated between 2°C and 8°C. Once in use, semaglutide pens may be stored at room temperature for a limited period, the exact window is stated in the Patient Information Leaflet and the SmPC on the eMC, and that is the document to follow, not general estimates online.

Side effects during a switch tend to follow the GI pattern common to GLP-1 medicines: nausea, changes in bowel habit, and reduced appetite are most noticeable in the early weeks of a new titration. Restarting from the beginning of the semaglutide ladder rather than jumping to a middle dose is partly why prescribers take that conservative approach, it reduces the likelihood of a difficult adjustment period. The broader comparison between liraglutide and semaglutide covers tolerability differences in more detail.

What Is Licensed for Weight Loss in the UK, and Where Semaglutide Sits

Both liraglutide (Saxenda) and semaglutide (Wegovy) hold UK licences for weight management in adults with a BMI of 30 or above, or 27 and above with at least one weight-related condition. Ozempic is also semaglutide, but it is licensed for type 2 diabetes, not weight loss, the distinction matters clinically and legally. Tirzepatide (Mounjaro) is a separate dual-agonist medicine with its own licence and typically higher average weight-loss figures in head-to-head evidence; that comparison lives on the Mounjaro-to-Wegovy switching page for readers weighing that option.

Retatrutide is a next-generation triple-agonist still in trials, not yet licensed in the UK. Anyone curious about where the landscape is heading can read the semaglutide-to-retatrutide overview, which explains the current research status clearly.

For people considering Wegovy specifically, the cost context is worth understanding before starting a consultation. The Wegovy cost page covers what private treatment typically involves and what should be included in any legitimate price. Whether Wegovy is the right medicine after liraglutide is a question a prescriber settles with you, not something a page can answer. Our clinical team's approach is described on the clinical team profile. If you are ready to explore your options, the place to begin is a free consultation with our prescribers.