Liraglutide (Victoza, Saxenda): what it is, how it works, results and side effects

What is liraglutide?

Liraglutide is the medicine. Victoza and Saxenda are two brand names for it, made by Novo Nordisk, at different doses for different uses.^1,2

Every medicine has two kinds of name. The medicine's own name says what works in your body. The brand is the name the company prints on the box.

Victoza and Saxenda come in the same kind of pen, with the same strength of liquid (6 mg in each mL). The difference is the dose the pen gives and what each brand is approved for.^1,2 A third Novo Nordisk brand, Xultophy, combines liraglutide with a long-acting insulin in one daily injection for type 2 diabetes.²¹

The US first approved liraglutide in 2010.¹ Other companies now make their own versions in several countries. A generic is a copy that a regulator has checked against the original brand.^16,17

Liraglutide and its brands. Names vary by country.

Names only, not a recommendation. Which brands are sold, and what they're approved for, differs by country.

Liraglutide belongs to the same family as semaglutide (Ozempic, Wegovy, Rybelsus), dulaglutide (Trulicity) and, partly, tirzepatide (Mounjaro, Zepbound). It is older than all of them, and it's the only one in this group you inject every day.^1,11

How does it work in your body?

It copies GLP-1, a hormone your gut releases after you eat. Your own GLP-1 is broken down in 1.5 to 2 minutes. Liraglutide is 97% the same, but changed so it lasts much longer: half of each dose is still in your blood after about 13 hours.²

The EU Saxenda label says people lose weight mainly because they eat less: it raises feelings of fullness and lowers hunger. It doesn't make the body burn more energy than a dummy injection does.³ Most of the weight lost is fat, with a bigger drop in the fat around the organs than in the fat under the skin.³

The extra insulin fades as blood sugar comes back towards normal.¹ The labels warn about low sugar mainly when liraglutide is taken with insulin or with sugar pills called sulfonylureas.^1,2

Who is it for?

Victoza is for people with type 2 diabetes. Saxenda is for weight management in adults with obesity, or with overweight plus a weight-related health problem. Both are added to diet and exercise, not used instead of them.^1,2,3

Doctors often use BMI (body mass index: your weight in kg divided by your height in metres, squared) to describe weight. These are the label thresholds in the US and EU:^2,3

• Saxenda, adults: a BMI of 30 or more, or 27 or more with at least one weight-related condition. The EU label names prediabetes or type 2 diabetes, high blood pressure, high cholesterol and sleep apnoea.^2,3
• Saxenda, ages 12–17: obesity and a body weight over 60 kg (132 lb).^2,3
• Saxenda, ages 6–11 (EU only): obesity and a body weight of 45 kg (99 lb) or more.³
• Victoza: type 2 diabetes, at any weight, from age 10.^1,4

Many Asian guidelines use lower cut-offs. A World Health Organization expert group found that many Asian people have a high risk of type 2 diabetes and heart disease at BMIs below the usual cut-off of 25.²³ In India, for example, obesity starts at a BMI of 25.²⁴ The surgery guideline above lowers its own threshold to 27.5 for Asian people.²⁵ Indian BMI cut-offs explained.

These thresholds are points where you and a doctor can start a conversation. They aren't rules that say you must, or may, take a medicine.

Using Victoza for weight: "off-label"

A medicine's label is the official document that says what it's approved for, at what dose. Using it for something else, or at a different dose, is called off-label use.²² Victoza isn't approved for weight loss, so prescribing it for weight alone is off-label.¹

The rules differ by country. In the US, the FDA says doctors may generally prescribe an approved medicine off-label when they judge it right for the patient. It also says the FDA hasn't decided whether the medicine is safe and effective for that use.²² Ask your doctor why they're choosing one brand or dose over another.

How do you take it?

One injection under the skin of the belly, thigh or upper arm, once a day. You can take it at any time of day, with or without food. You start low and go up each week.^1,2

Why every day? About half of a dose is gone from your blood after 13 hours.¹ The US label says this profile is what makes it suitable for once-a-day dosing.¹ By comparison, semaglutide (Wegovy) lasts about a week, so it's injected weekly.²⁶

Why start low? The first, lowest dose isn't meant to work. It's there to lower the risk of stomach side effects while your body gets used to the medicine.¹

The full Saxenda dose (3 mg) is 1.2 mg higher than Victoza's highest (1.8 mg).^1,2 Both brands warn against taking two liraglutide products together.^1,2

How long a pen lasts. Each pen holds 18 mg (3 mL of 6 mg/mL).¹ So one pen lasts 15 days at 1.2 mg, 10 days at 1.8 mg and 6 days at 3 mg. Once opened, a pen must be thrown away after 30 days, even if some is left.^1,2

What results can you expect?

For weight, adults in the main trial lost about 8% of their body weight on Saxenda 3 mg, against about 3% on a dummy injection. For type 2 diabetes, Victoza lowers HbA1c and cut heart problems in a large trial.^3,8

Most numbers below come from randomised trials. Each one worked the same way:

• People were split at random into groups. One group got the medicine; another got a dummy injection (placebo) with no medicine in it.
• Both groups got the same diet and exercise advice, and nobody knew which injection they were on.
• So the gap between the groups is what the medicine itself added.^5,6

Novo Nordisk, which makes Victoza and Saxenda, paid for SCALE Obesity and Prediabetes, SCALE Teens and SCALE Kids, and co-funded LEADER.^5,7,8,9,10

Weight

Average weight lost, as a share of body weight. Kilograms are for someone who starts at 90 kg (198 lb).

These are averages. Some people lose much more, and some lose very little. In SCALE, 63 in 100 people on liraglutide lost at least 5% of their weight, against 27 in 100 on the dummy injection. About 33 in 100 lost more than 10%, against 11 in 100.⁵ Put the other way, about 37 in 100 on liraglutide lost less than 5%.

Early response predicts later response. In the EU label's analysis, people who had lost at least 5% after 12 weeks on the full dose were predicted to lose about 11% at one year. Of those who hadn't, 93 in 100 didn't reach a 10% loss at one year.³ That's why the labels say to stop if it isn't working (see Stopping).

Over 3 years, in people with prediabetes. Prediabetes means blood sugar higher than normal, but not yet diabetes. In the 2,254 people in SCALE who had it, the liraglutide 3 mg group had lost 6.1% of their weight after 160 weeks, against 1.9% on the dummy injection.⁷ While on treatment, 2 in 100 were diagnosed with type 2 diabetes, against 6 in 100.⁷ About half of the people left the trial early and weren't followed up, so the authors say these results have that limit.⁷

Teenagers and children

Children are still growing, so these trials measured BMI rather than weight alone.^9,10

Out of every 100 young people, how many lowered their BMI by at least 5%:

Stomach side effects were more common in young people on liraglutide: 65 in 100 teenagers had them, against 37 in 100 on the dummy injection.⁹ In children aged 6–11 it was 80 in 100, against 54 in 100.¹⁰ The US approves Saxenda from age 12; the EU also approves it for children aged 6–11.^2,3 In the EU, a doctor experienced in treating childhood obesity should start it for children under 12.³

Blood sugar in type 2 diabetes

HbA1c is a blood test that shows your average blood sugar over about the past 2–3 months.²⁸ In diabetes, a lower number is usually the goal.

In children aged 10–17 with type 2 diabetes, HbA1c ended 1.06 points lower on Victoza than on a dummy injection after 26 weeks, with both groups also taking metformin.¹

Heart: the LEADER trial

Out of every 100 people, how many had a heart attack, a stroke or died of heart or blood-vessel disease:

Based on LEADER, the US approves Victoza to lower the risk of heart attack, stroke and heart-related death in adults with type 2 diabetes and heart disease.¹ LEADER tested the 1.8 mg diabetes dose in people with diabetes. It doesn't tell us the heart effect of Saxenda 3 mg in people without diabetes. LEADER was paid for by Novo Nordisk and the US National Institutes of Health.⁸

Compared with the weekly medicines

Separate trials can't be compared fairly, because they enrol different people. But two trials tested liraglutide head to head against semaglutide, in the same people.^11,12

So, honestly: liraglutide is older and, on average, less effective for weight than weekly semaglutide.¹¹ In 2025 Novo Nordisk decided to stop selling Saxenda in Australia after December 2025, pointing to STEP 8 and to Wegovy.²⁰ For tirzepatide, see the tirzepatide page.

Liraglutide still has things going for it. It has been used since 2010, and LEADER showed a heart benefit in type 2 diabetes.^1,8 Other makers sell their own versions in the US, the EU and India.^16,18,19 And in the EU, Saxenda is approved for children from age 6.³ Which medicine fits depends on your health, what's available and what you can afford, so it's a choice to make with a doctor.

What are the common side effects?

Stomach and gut effects: feeling sick (nausea), diarrhoea, constipation and vomiting. They're most common in the first weeks and while the dose goes up, and they're more common at Saxenda's higher dose.^1,2,6

People on a dummy injection get some stomach symptoms too. So the real effect of the medicine is the difference between the two numbers.

Out of every 100 people, how many felt sick (nausea) at some point:

Most stomach effects were mild or moderate, and nausea became less common as treatment went on.² Still, about 10 in 100 adults stopped Saxenda because of side effects, against 4 in 100 on the dummy injection. Most who stopped did so in the first few months.² The two cards above come from different trials with different people and doses, so they show the size of the effect, not a fair comparison between brands.

Side effects at a glance

How often each common side effect happened on liraglutide and on a dummy injection.

Saxenda: pooled adult weight trials on the US Saxenda label. Victoza: pooled type 2 diabetes trials on the US Victoza label. Saxenda rows are 3 mg; Victoza rows are 1.8 mg. Rounded to whole numbers. Different trials, so don't compare the two rows.^1,2

What helps with nausea. An expert advisory from four US obesity and nutrition societies suggests eating smaller meals, going easy on fatty food, drinking enough fluids and keeping alcohol low.¹⁵ If a dose step is too hard, the Saxenda label lets your doctor delay the next one by about a week.² Don't change your dose on your own.

Will I lose muscle? Protein and exercise

Some of any weight you lose is lean mass, which includes muscle. The EU label says liraglutide's weight loss is mainly fat. Protein and strength exercise help protect muscle.^3,15

One liraglutide trial tested exercise directly. In Denmark, 195 adults first lost about 13 kg on a low-calorie diet, then spent a year on exercise, liraglutide 3 mg, both, or neither.¹³ Exercise plus liraglutide cut body fat by 3.9 percentage points. That was about twice as much as exercise alone (1.7) or liraglutide alone (1.9).¹³

A smaller appetite makes protein easier to miss. The advisory suggests eating protein-rich foods first in a meal.¹⁵ Four of its 18 authors declare roles with Novo Nordisk and five with Eli Lilly.¹⁵

Serious risks, and who shouldn't take it

Serious problems are less common, but you should know the warning signs. Most come from the labels' official warnings.^1,2

Frequency words below are the EU label bands: common means 1 in 10 to 1 in 100 people; uncommon, 1 in 100 to 1 in 1,000; rare, 1 in 1,000 to 1 in 10,000; very rare, fewer than 1 in 10,000.³ The bands differ between brands, so each one names its source.

Who shouldn't take it

• People with a personal or family history of medullary thyroid cancer, or with MEN 2.^1,2
• Anyone who has had a serious allergic reaction to liraglutide.²
• Women who are pregnant or trying to become pregnant.³
• People with severe gastroparesis, where the stomach empties very slowly: the labels don't recommend it.^1,2
• People already on another GLP-1 medicine: Saxenda shouldn't be combined with one.²

What happens when you stop?

The labels tell doctors to stop Saxenda if it isn't working by a set point. And when people stop, weight tends to come back.^2,3,14

When the labels say to stop

• US, adults: check weight 16 weeks after starting. Stop if you haven't lost at least 4% of your starting weight, because you're unlikely to get a useful result.²
• EU, adults: stop after 12 weeks on the full 3 mg dose if you haven't lost at least 5%.³
• Children and teenagers: stop or rethink if BMI hasn't fallen by at least 1% after 12 weeks on the full dose (US), or 4% (EU).^2,3

For someone starting at 90 kg (198 lb), 4% is about 3.6 kg (8 lb) and 5% is 4.5 kg (10 lb).

Does the weight come back?

Often, yes. In the Danish trial above, people who had liraglutide alone for a year regained weight in the year after it stopped. Those who had done supervised exercise alone kept their weight steady.¹⁴ Adding exercise to liraglutide meant 2.5 kg less regain than liraglutide alone, a gap that could be chance.¹⁴ Only 109 of the 195 people came back to be weighed, so this is a small result.¹⁴ In SCALE Teens, BMI went up again in the 26 weeks after liraglutide stopped.⁹

Don't stop without talking to your doctor.³ Our guide to stopping covers this for all GLP-1 medicines.

Missed doses, storage and injecting

Missed one dose? Don't double up. Missed more than 3 days? Start again at the lowest dose.^1,2

If you miss a dose

• US labels: skip it and take your next dose at the usual time. Don't take an extra dose or a bigger one to make up.^1,2
• EU Saxenda label: if you remember within 12 hours of your usual time, take it then. If it's later than that, skip it and take the next one the following day.³
• More than 3 days missed: the US labels say to restart at 0.6 mg and step up again, to lower the risk of stomach side effects. Ask your doctor how to restart.^1,2

Storing your pens

• New pens: in the fridge, at 2–8 °C (36–46 °F). Not in the freezer or next to the cooling element. Never use a pen that has frozen.¹
• The pen you're using: up to 30 days at room temperature, 15–30 °C (59–86 °F), or in the fridge. The EU label says below 30 °C.^1,3
• Keep the cap on and the pen out of heat and sunlight.¹

Injecting

• Use a new needle each time, and take it off after injecting.¹
• Never share a pen, even with a new needle.¹
• Only use the liquid if it's clear and colourless.¹
• Change the injection spot within the same area each day.²
• If you also take insulin, give it as a separate injection. Never mix them.¹

In your country

Brands, prices and who can prescribe differ by country, so they're on our country pages.

Questions people ask