Saxenda vs Wegovy: Which weight loss injection is right for you?

DoktorABC editorial team

Accurate, up-to-date health information written by our editorial team and reviewed by UK-registered prescribers.

What is Saxenda?

Saxenda is the brand name for liraglutide 3 mg, a once-daily injectable GLP-1 receptor agonist manufactured by Novo Nordisk. It was the first GLP-1 medicine licensed specifically for weight management and has been available in the UK since 2015. Saxenda is licensed by the MHRA for chronic weight management in adults with a BMI of 30 kg/m² or above, or 27 kg/m² or above with at least one weight-related health condition such as high blood pressure, type 2 diabetes, or sleep apnoea. It is also licensed for use in adolescents aged 12-17 with obesity, which Wegovy currently is not.

Treatment starts at 0.6 mg daily and increases weekly over four weeks to the maintenance dose of 3 mg per day. Saxenda is injected once daily, at any time of day, into the abdomen, upper arm, or outer thigh.

What is Wegovy?

Wegovy is the brand name for semaglutide 2.4 mg, a once-weekly injectable GLP-1 receptor agonist, also manufactured by Novo Nordisk. It is licensed by the MHRA for chronic weight management in adults with a BMI of 30 kg/m² or above, or 27 kg/m² or above with at least one weight-related health condition. Wegovy received NICE approval for use within specialist NHS weight management services under Technology Appraisal TA875 in March 2023.

Treatment starts at 0.25 mg per week and increases gradually over 16-20 weeks to the standard maintenance dose of 2.4 mg. A higher dose of 7.2 mg was approved by the MHRA on 6 January 2026 for patients with a BMI of 30 or above who have reached and tolerated the 2.4 mg dose. For most people in the UK, access is currently via private prescription.

What are the key differences between Saxenda and Wegovy?

Though both are GLP-1 receptor agonists licensed for weight loss, the differences between them are clinically meaningful and affect everything from injection frequency to expected outcomes.

Saxenda vs Wegovy vs Mounjaro: Three-way comparison

For patients comparing all three major injectable weight loss treatments currently available in the UK, the table below provides a direct overview.

Prices based on GPhC-registered UK provider data, April 2026.

At standard licensed doses, Mounjaro produces the greatest average weight loss, followed by Wegovy, with Saxenda producing the most modest results. The cost picture broadly reflects this, with Saxenda typically the most affordable private option and Mounjaro the most expensive following Eli Lilly's September 2025 price increase.

Which is more effective for weight loss: Saxenda or Wegovy?

Wegovy produces significantly greater weight loss than Saxenda. The most direct evidence comes from the STEP 8 trial, a head-to-head comparison published in JAMA in 2022, which compared semaglutide 2.4 mg (Wegovy) directly against liraglutide 3 mg (Saxenda) over 68 weeks in adults with overweight or obesity without diabetes.

What do the clinical trials show?

The STEP 8 trial results are striking. Participants on Wegovy lost an average of 15.8% of their starting body weight, compared to 6.4% on Saxenda. Nearly 71% of Wegovy users achieved at least 10% weight loss, compared to 26% of those on Saxenda.

The SCALE Obesity and Prediabetes trial, the landmark study for Saxenda, enrolled 3,731 adults over 56 weeks and found average weight loss of approximately 8% of starting body weight, compared to 2.6% with placebo. Around 63% of participants achieved at least 5% weight loss. These results demonstrate that Saxenda is effective compared to no treatment, but the gap with Wegovy is considerable.

Why does Wegovy produce better results?

The difference comes down to the active ingredient and its half-life (the time it takes for the body to reduce the concentration of a drug in the bloodstream by half). Semaglutide has a half-life of approximately seven days, which is why it can be injected once weekly and maintains more stable blood levels throughout the week. Liraglutide has a half-life of around 13 hours, which is why it requires daily injections. The more potent and sustained appetite suppression achieved with semaglutide at Wegovy's doses is the primary driver of its superior weight loss outcomes.

Saxenda vs Wegovy side effects: how do they compare? 

The side effect profiles of Saxenda and Wegovy are broadly similar, as both activate GLP-1 receptors. Gastrointestinal effects like nausea, diarrhoea, vomiting, and constipation are the most common with both. Because Wegovy is used at higher doses, these effects can be more pronounced, particularly during the titration phase.

Both medicines share the same serious contraindications: they must not be used by anyone with a personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia type 2 (MEN 2), and neither should be used during pregnancy or breastfeeding.

One practical difference is injection frequency. Because Saxenda is injected daily, injection-site reactions may occur more frequently than with Wegovy's once-weekly schedule. Rotating sites consistently can help minimise this for both treatments.

Both Saxenda and Wegovy carry the Black Triangle symbol (▼), meaning the MHRA actively encourages reporting of suspected side effects via the Yellow Card scheme at yellowcard.mhra.gov.uk.

How much do Saxenda and Wegovy cost in the UK?

What does Saxenda cost privately?

Saxenda is typically the more affordable of the two treatments on a private prescription. Monthly costs for the maintenance dose of 3 mg daily are approximately £150 to £200, depending on the provider. Because Saxenda is a daily injection, a full month's supply requires more pens than a weekly injection, which is reflected in the monthly cost.

H3: What does Wegovy cost privately?

Private Wegovy prescriptions typically cost between £169 and £289 per month at the standard 2.4 mg maintenance dose, rising to £250 to £340 for the new 7.2 mg dose available from January 2026. Costs are lower during the titration phase when starter doses are used.

What does each cost on the NHS?

For eligible patients, both medicines are available at the standard NHS prescription charge of £9.90 per item in England. Prescriptions are free in Scotland, Wales, and Northern Ireland for eligible patients.

However, NHS access differs between the two. Wegovy is available through specialist NHS weight management services under NICE TA875 for patients who meet the eligibility criteria. Saxenda is not routinely commissioned by most NHS integrated care boards for weight management, meaning it is less consistently available on the NHS than Wegovy, even for patients who might otherwise qualify. Speak to your GP about which pathway may be most relevant to your situation.

Is Saxenda cheaper than Wegovy overall?

Saxenda has a lower monthly price tag in private prescription comparisons. However, given that Wegovy produces substantially greater weight loss in clinical trials, the cost-per-outcome calculation is more complex than a headline price comparison suggests. For patients for whom Wegovy is clinically appropriate, the greater efficacy may represent better long-term value despite the higher monthly cost. This is a conversation worth having with your prescriber.

Which treatment is right for you: Saxenda or Wegovy?

Neither medicine is the right choice for every person. The decision depends on your individual health profile, treatment history, injection preference, budget, and clinical goals.

When might Saxenda be worth discussing?

• You are between 12 and 17 years old (Saxenda is licensed for this age group; Wegovy is not)
• You prefer the flexibility of daily dosing, for example if you want more granular control over adjustments
• You have previously tried and not tolerated semaglutide
• Wegovy is unavailable or unaffordable and Saxenda is a clinically appropriate alternative
• Your prescriber has assessed Saxenda as more suitable given your medical history

When might Wegovy be worth discussing?

• You want the treatment with the strongest clinical evidence base for weight loss at standard licensed doses
• You prefer once-weekly injections over daily injections
• You may be eligible for NHS access through a specialist weight management service
• You are considering the higher 7.2 mg dose option for greater results
• You have already tried Saxenda with limited results and want to discuss an alternative

What if neither feels right?

Mounjaro (tirzepatide) is the third major option and produces the greatest average weight loss of the three treatments currently available in the UK. It is available through specialist NHS services from June 2025 under NICE TA1026, and via private prescription. Your prescriber can advise on whether Mounjaro may be more appropriate for your circumstances.

In all cases, the most important step is a thorough assessment with a UK-registered prescriber who can evaluate your full health history, current medications, and realistic treatment goals before recommending any of these medicines.

Final thoughts

Saxenda and Wegovy are both legitimate, MHRA-licensed options for weight management in the UK. The clinical evidence consistently shows that Wegovy produces greater average weight loss, and its once-weekly injection schedule offers a practical advantage for many patients. Saxenda remains a valid option in specific clinical situations, particularly for adolescents and patients who are not suitable candidates for semaglutide.

Cost, injection frequency, and NHS availability are all relevant factors, but they should sit alongside clinical appropriateness rather than replace it as the basis for a treatment decision. The right starting point is always a conversation with your GP or a UK-registered prescriber.

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The DoktorABC medical advisory board

Dr. Roland Ruiken

Medical advisor, Norway

Dr. Viktor Simunovic

Medical advisor, Croatia

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