What is Saxenda (Liraglutide)?

Saxenda is the brand name for liraglutide, a medicine given as a daily injection from a pre-filled pen. It is licensed in the UK for weight management. It is a prescription-only medicine, which means nobody here can lawfully supply it to you until a prescriber has assessed you.

Disclaimer: PenCompare is an independent comparison platform. This guide is for information only. It is not medical advice, not a recommendation to take any medicine, and no substitute for an assessment by a qualified prescriber.

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What Saxenda actually is

Saxenda is a trade name. The medicine inside it is liraglutide, and that is the word worth holding on to, because it is what tells you whether two products you are comparing contain the same thing. Like semaglutide, liraglutide is a GLP-1 receptor agonist — but it is an older one, and it is taken differently.

It is supplied as a pre-filled pen and injected under the skin once a day, at roughly the same time each day. Treatment starts at a low dose and increases in steps under the prescriber’s direction, which is how side effects are managed. Our Saxenda dosage guide sets out the five strengths and why a daily pen reaches full strength so much faster than a weekly one.

Daily, not weekly

This is the difference most worth understanding before you compare prices, because it is the one a price table cannot show you.

Daily

  • Liraglutide, the ingredient in Saxenda
  • One injection every day, at roughly the same time
  • Around 365 injections in a year

Weekly

  • Semaglutide and tirzepatide, the ingredients in Wegovy and Mounjaro
  • One injection a week, on the same day
  • Around 52 injections in a year
Neither column is the wrong answer, which is why neither is marked as one. Two medicines can cost within a few pounds of each other a month and still ask very different things of the person taking them — and a price table cannot show that.

Neither pattern is better in the abstract. A daily injection is a daily routine to keep, and for some people that is harder to sustain over months. For others a daily dose is easier to fit around life than remembering one fixed day each week, and a shorter-acting medicine can be simpler to stop if it does not suit them. What matters is that the difference is real and belongs in the decision, rather than being discovered after the first order.

How it works

Liraglutide imitates GLP-1, a hormone the body releases after eating. Acting on GLP-1 receptors in the brain, it increases the feeling of fullness and reduces hunger, so people tend to eat less without having to hold that decision in mind all day. It is the same mechanism as semaglutide, the ingredient in Wegovy, and it does not act on the second hormone that tirzepatide, the ingredient in Mounjaro, works on as well.

What the clinical trials measured

The trials usually quoted are the SCALE programme, published in the New England Journal of Medicine in 2015. Participants taking liraglutide alongside lifestyle support lost in the region of 5% to 10% of their body weight over 56 weeks.

Placed next to the figures quoted for the weekly pens, that is a smaller number, and it is fair to say so plainly: on average liraglutide produces less weight loss than semaglutide or tirzepatide. Two things are worth adding, because a single number decides less than it appears to:

  • These are averages from separate trials, with different participants and different durations. They are not head-to-head results, so the gap between the headline figures is not a precise measure of the gap between the medicines
  • A medicine someone can tolerate and keep taking does more than one they stop after a month. Suitability, side effects and supply all matter, and none of them appears in a percentage

Who it is prescribed for in the UK

For weight management, liraglutide is generally considered for adults who meet a body-mass-index threshold:

  • A BMI of 30 or above
  • A BMI of 27 or above together with a weight-related health condition, such as pre-diabetes or raised blood pressure

Meeting a threshold is where an assessment starts, not where it ends. A prescriber also has to consider your medical history, any other medicines you take, and whether treatment is appropriate at all. There are people for whom it is not.

At a glance

  • Active ingredient: liraglutide
  • Form: pre-filled pen, injected under the skin
  • Frequency: once daily, at roughly the same time each day
  • Class: GLP-1 receptor agonist
  • Legal status: prescription-only medicine (POM)
  • Average weight change in the SCALE trials: around 5% to 10% over 56 weeks

If you already have a prescription and want to see what UK providers charge, our Saxenda price comparison lists the complete cost for each dose, including consultation and delivery fees, alongside the date each price was last checked. We are a comparison service, not a pharmacy, and we do not supply medicines.

Frequently asked questions

Usually it is not a free choice. Availability, suitability and what a prescriber judges appropriate all narrow the options, and the weekly pens have spent long stretches in short supply. Some people also prefer a shorter-acting medicine, because if it does not suit them it clears more quickly. The decision belongs with a prescriber who knows your history.

They contain the same ingredient, liraglutide, but they are licensed for different purposes and use different dose ranges. Saxenda is the one licensed in the UK for weight management. It is the same pattern as Wegovy and Ozempic, and the same caution applies: a cheaper pen carrying a different brand name is not the same product at a discount. Our guide to buying medicines online safely sets out what else is worth checking before you order.

No. It is a prescription-only medicine, so it can be supplied in the UK only against a valid prescription issued by someone with UK prescribing rights, and dispensed by a registered pharmacy. A site offering it without those steps is not operating lawfully, and what arrives may not be what the box says it is.

The commonly reported effects are gastrointestinal — nausea, diarrhoea, constipation and vomiting — and are one reason the dose is increased gradually. Less common but more serious effects exist. The authoritative list for any specific pen is the patient information leaflet supplied with it and the summary of product characteristics, and anything worrying should go to your prescriber or pharmacist rather than to a comparison site. Suspected side effects can be reported through the MHRA Yellow Card scheme. Our guide to Saxenda side effects covers what is commonly reported, and the signs that need urgent medical help rather than patience.

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