Saxenda versus Wegovy: what the evidence actually shows

You're weighing up two injections and wondering whether you've been on the wrong one

That's a reasonable place to be. Saxenda has been available in the UK since 2015 and many people have a year or more of experience with it. Wegovy arrived later but with a noticeably stronger evidence base, and it's the one GLP-1 weight-management injection that most UK prescribers now reach for first when the trial data is the deciding factor.

Both medicines mimic a gut hormone called GLP-1, which signals fullness and slows how quickly your stomach empties. The practical effect (eating less without feeling deprived) is broadly similar. Where they part company is on dose frequency, the depth of weight loss recorded in trials, and tolerability patterns. Saxenda is a daily subcutaneous injection; Wegovy is once weekly. For anyone who found the daily routine of saxenda demanding, that difference alone shifts the equation, and our Saxenda vs Wegovy comparison walks through each of those differences in full. You can read more about how semaglutide works on the Wegovy overview page.

It's also worth knowing that liraglutide (saxenda) is not the same as Ozempic. If you've seen those names used interchangeably online, the Ozempic versus Wegovy comparison explains the distinction clearly, they are different molecules with different licensed uses.

What the trial numbers say (and what they don't

The STEP 1 trial) 1,961 adults with obesity, 68 weeks, semaglutide 2.4 mg versus placebo, recorded an average weight reduction of around 15%, as published in the New England Journal of Medicine. Saxenda's pivotal trials reported roughly 7–8% average loss at 3 mg over 56 weeks. These studies used different populations and protocols, so a direct head-to-head reading overstates the precision, but the direction of the gap is consistent and reflected in NICE's own appraisals.

NICE recommends Wegovy (TA875) within specialist weight management services and subject to a two-year treatment limit. Saxenda does not have an equivalent current NICE technology appraisal recommending it in the same way. The NICE appraisal of semaglutide (TA875) sets out the eligibility criteria in detail, including BMI thresholds and the requirement for a weight-related comorbidity in most cases.

The comparison table below summarises the headline differences. Numbers are drawn from published trial data and regulatory documentation.

Side effects, tolerability and who these medicines suit

The side-effect profile of both medicines is dominated by the gut: nausea, vomiting, constipation and diarrhoea are the most commonly reported effects for each. They tend to be most noticeable at the start of treatment or after a dose increase, and they usually settle. Because saxenda is titrated daily and reaches its maintenance dose over several weeks, some patients find the adjustment period more drawn-out than with Wegovy's four-weekly steps. Others find the finer daily control easier on their system. Neither experience is wrong, it's individual.

The NHS medicines page for semaglutide covers Wegovy's side-effect profile in plain language. For pancreatitis specifically, the MHRA issued a Drug Safety Update in January 2026 highlighting it as a known but uncommon risk across the GLP-1 class, severe, persistent stomach pain that radiates to the back is a reason to seek urgent medical help.

Contraception is worth flagging if you are using the oral contraceptive pill alongside tirzepatide (Mounjaro rather than Wegovy), but the same concern is less strongly evidenced for semaglutide. Still, any medicine interaction question should go to your prescriber rather than a comparison page. If you're considering switching from saxenda to Wegovy, that conversation is exactly what a free consultation with nume's prescribers is designed for.

What's licensed for weight loss in the UK right now, and what nume dispenses

Saxenda is a licensed UK weight-management medicine. nume does not dispense it. The two medicines nume's GPhC-registered pharmacy does dispense for weight management are Wegovy (semaglutide, in injection and (as of June 2026) tablet form) and Mounjaro (tirzepatide), which is the only dual GIP and GLP-1 receptor agonist licensed in the UK. If you've found the results of saxenda modest and want to understand which option might suit you better, our guide to whether Wegovy is better than Saxenda goes deeper on how the two medicines compare before you decide on next steps.

A note on Ozempic: it is also semaglutide, but it is licensed for type 2 diabetes, not weight management. It is not interchangeable with Wegovy for weight-loss purposes, and prescribing it off-label for weight loss is a separate clinical discussion entirely, and if you want a thorough breakdown of how the two active ingredients differ, our guide comparing semaglutide and saxenda covers the key distinctions in detail. The Ozempic versus Wegovy for weight loss page addresses that distinction head-on.

Which medicine suits you is not something a table can settle. It is a clinical decision shaped by your BMI, your health history, how your body has responded to any previous treatment, and your preferences. Our prescribers make that assessment with you. Check your eligibility and start a free consultation, a named clinician, not an algorithm, reviews every submission the same day.