Saxenda and Victoza (liraglutide): research, side effects and approved dosing
In short
Liraglutide is a peptide medicine acting on the GLP-1 receptor, with an EU marketing authorisation for weight management (Saxenda) and type 2 diabetes (Victoza) [3, 4]regulator. Its effect has been tested in large randomised human trials [1, 2]A.
- In the SCALE trial body weight fell over 56 weeks by a mean of 8.4 kg with liraglutide and 2.8 kg with placebo [1]A. The EMA considers the effect modest but clinically relevant [3]regulator.
- In the LEADER trial people with diabetes had fewer cardiovascular events on liraglutide (13.0%) than on placebo (14.9%) [2]A.
- The most common side effects are nausea, vomiting, diarrhoea and constipation. Gallstones were more frequent than with placebo in trials [3]regulator [5]official.
- Saxenda and Victoza are available only with a prescription [3, 4]regulator. In Finland liraglutide is in Annex 1 of the medicines list, so it is controlled as a medicine [7]regulator. Fimea warns against injectable peptides bought online [6]regulator.
What is liraglutide?
Liraglutide is a GLP-1 receptor agonist, a medicine that acts on the same receptor as the body's own hormone GLP-1 [3]regulator. It is a prescription medicine with a marketing authorisation in the EU [3, 4]regulator.
Which is which in the EU: Saxenda (liraglutide) is a weight management medicine [3]regulator, and Victoza (liraglutide) is a type 2 diabetes medicine [4]regulator. Both are injected under the skin once a day with a prefilled pen [3, 4]regulator. Ablymico (liraglutide) is a hybrid medicine of Saxenda for weight management, with an EU marketing authorisation since 15 Jul 2026 [11]regulator; whether it is sold in Finland is covered in Weight-loss drug cost and prescription.
A product sold online "for research use" is not the same thing as the pharmacy medicine. According to Fimea, "for research use only" means the product is not intended for humans [6]regulator. All GLP-1 drugs side by side: Weight-loss drugs (GLP-1). All substances: Peptides A-Z.
Evidence at a glance
Each cell gives the kind of study and its source. The letter is the evidence level, not the result.
| Claimed effect | Humans | Animals | Cells |
|---|---|---|---|
| Weight loss | 3,731 adults, 56 weeks: -8.4 kg with liraglutide and -2.8 kg with placebo [1]A | - | - |
| Preventing diabetes in prediabetes | 160 weeks: diabetes in 2% on liraglutide and 6% on placebo; about half withdrew [8]A | - | - |
| Heart and blood vessels (type 2 diabetes) | 9,340 patients, median 3.8 years: event in 13.0% and 14.9% [2]A | - | - |
| Blood glucose (type 2 diabetes) | Authorised treatment for adults and from 10 years (Victoza) [4]regulator | - | - |
| Children and adolescents (obesity) | Authorised under set conditions; according to the EMA it is not clear whether the lower BMI brings a health benefit [3]regulator | - | - |
| Weight after stopping | Adults (S-LiTE): in the year after stopping, 6.0 kg more regain after liraglutide than after an exercise programme [10]A; adolescents: weight began to come back during 26 weeks of follow-up [5]official | - | - |
| Safety | Gastrointestinal effects common; more gallstones than with placebo; pancreatitis uncommon [1]A [5]official | - | - |
"-" = no such study is known.
What is liraglutide used for?
Liraglutide is used for weight management and for type 2 diabetes. The indications are authorised by the EMA [3, 4]regulator.
- Weight management, Saxenda: alongside diet and exercise for adults with a BMI of 30 or more, or 27 to 30 plus a weight-related condition. Under set conditions also for adolescents from 12 years and children aged 6 to 11 with obesity [3]regulator.
- Type 2 diabetes, Victoza: for adults and children from 10 years of age [4]regulator.
Saxenda received an EU-wide marketing authorisation on 23 March 2015 [3]regulator and Victoza on 30 June 2009 [4]regulator. Prices and how to get a prescription are covered in Weight-loss drug cost and prescription.
How does liraglutide work?
Liraglutide acts like the body's own hormone GLP-1, which regulates appetite. According to the EMA it is thought to increase the feeling of fullness and reduce hunger and cravings, so that less food is eaten [3]regulator.
In diabetes, liraglutide increases the insulin released by the pancreas after a meal, which helps keep blood glucose under control [4]regulator.
Has liraglutide been studied in humans?
Yes, liraglutide has been studied extensively. The SCALE and LEADER trials covered on this page alone enrolled more than 13,000 participants [1, 2]A. The results are group averages and do not transfer as such to an individual or to a product bought online.
Weight: the SCALE trial
In the SCALE Obesity and Prediabetes trial, 3,731 adults without type 2 diabetes received liraglutide or placebo for 56 weeks alongside lifestyle counselling. Participants had a BMI of at least 30, or at least 27 plus abnormal blood lipids or high blood pressure. Body weight fell by a mean of 8.4 kg with liraglutide and 2.8 kg with placebo [1]A.
At least 5% of body weight was lost by 63.2% of the liraglutide group and 27.1% of the placebo group. More than 10% was lost by 33.1% and 10.6% [1]A.
Pooling five main studies, the EMA found that Saxenda reduced body weight by 7.5%, against 2.3% with placebo. According to the EMA the effect is modest, particularly in men, but clinically relevant [3]regulator.
Prediabetes: the three-year continuation
In the 160-week continuation in adults with prediabetes, body weight had fallen by a mean of 6.1% with liraglutide and 1.9% with placebo. Diabetes was diagnosed during treatment in 2% of the liraglutide group and 6% of the placebo group. About half of participants withdrew before week 160, and those who withdrew were not followed up [8]A.
Heart and blood vessels: the LEADER trial
In LEADER, 9,340 people with type 2 diabetes at high cardiovascular risk received liraglutide or placebo. The median follow-up was 3.8 years. Cardiovascular death, non-fatal heart attack or non-fatal stroke occurred in 13.0% of the liraglutide group and 14.9% of the placebo group. Cardiovascular deaths were 4.7% and 6.0% [2]A.
What happens on stopping
In the Danish S-LiTE trial, adults first lost weight on a low-calorie diet and were then randomly assigned to a year of liraglutide 3.0 mg, an exercise programme, both, or placebo. In the year after treatment ended, those who stopped liraglutide regained 6.0 kg more than those who stopped the exercise programme, and more of those who had combined exercise and liraglutide still kept a weight loss of at least 10% than of those who had liraglutide alone [10]A. In the three-year SCALE continuation, those who withdrew were not followed up [8]A. In a trial in adolescents, weight began to come back during 26 weeks of follow-up after treatment ended [5]official. More: Stopping weight-loss drugs.
Who is studying liraglutide?
The large liraglutide trials were run or funded by the manufacturer. The SCALE trials were funded by Novo Nordisk [1, 8]A, and LEADER by Novo Nordisk and the US National Institutes of Health [2]A. The marketing authorisations and product information are assessed by the European Medicines Agency [3, 4]regulator.
Who wrote this page: the editorial team
This page was written by the Molecular Recovery editorial team. The draft was made with the help of AI, and the claims were checked against the sources (AI policy). The page has not been medically reviewed. How we work: About us.
What side effects does liraglutide have?
The most common side effects are gastrointestinal. According to the EMA, the most common side effects of Saxenda (in more than 1 in 10 people) are nausea, vomiting, diarrhoea and constipation [3]regulator. The most common side effects of Victoza are nausea and diarrhoea, which usually pass after a few days or weeks [4]regulator.
In five placebo-controlled trials of Saxenda (5,813 adults), gastrointestinal effects occurred in 67.9%, mostly in the first weeks of treatment [5]official. In SCALE the side effects were mostly mild or moderate, and serious adverse events occurred in 6.2% of the liraglutide group and 5.0% of the placebo group [1]A.
What users report. In the Reddit accounts we compiled (not research), 123 of 188 people (65%) reported some harm, most often: nausea (33, 18%), constipation (17, 9%) and stomach pain or bloating (16, 9%). People tend to post when something goes wrong, so this share does not tell how common harms are. Liraglutide is a prescription medicine. The figures describe users' experiences, not treatment advice: we did not record doses, dose changes, where the medicine came from or how much weight was lost. Almost all accounts (205 of 206) came from the forum r/liraglutide. The harms in detail: Liraglutide user experiences.
Gallstones and gallbladder inflammation
According to the Saxenda summary of product characteristics, weight management trials showed more gallstones and gallbladder inflammation with liraglutide than with placebo. Substantial weight loss only partly explained the difference. Gallstones are classed as common (1 to 10 users in 100) and gallbladder inflammation as uncommon, and both can lead to hospital care and removal of the gallbladder [5]official.
Pancreatitis
According to the summary of product characteristics, acute pancreatitis has been observed with GLP-1 receptor agonists, and for Saxenda it is classed as uncommon (1 to 10 users in 1,000) [5]official. In LEADER, pancreatitis was slightly less frequent in the liraglutide group than in the placebo group, and the difference was not statistically significant [2]A. According to the Victoza summary of product characteristics, confirmed acute pancreatitis occurred in LEADER in 0.4% of the liraglutide group and 0.5% of the placebo group [9]official.
According to the package leaflet, severe and persistent abdominal pain that may reach the back, with nausea and vomiting, is a reason to contact a doctor straight away [5]official. More: Side effects and safety.
Interactions and who there are no data for
In people with type 2 diabetes, Saxenda is not used together with another GLP-1 receptor agonist [5]official. The key points of the Saxenda summary of product characteristics [5]official:
- Pregnancy: liraglutide is not used during pregnancy. If a patient wishes to become pregnant or pregnancy occurs, treatment is stopped [5]official.
- Breastfeeding: Saxenda is not used while breastfeeding, because there is no experience of it [5]official.
- Insulin and sulfonylureas: in type 2 diabetes the risk of low blood sugar may rise when liraglutide is used with insulin or a sulfonylurea. Reducing their dose is considered when treatment starts [5]official.
- Oral medicines: liraglutide slightly slows stomach emptying, which may affect the absorption of other medicines. In studies absorption was not delayed to a clinically relevant degree, and the effect of contraceptive pills is not expected to be reduced [5]official.
- Warfarin: INR is monitored more often when treatment starts [5]official.
- People over 75: experience is limited, and use of Saxenda is not recommended in them [5]official.
- Children under 10 and end-stage kidney disease: there are no data for Victoza in children under 10 and no treatment experience in end-stage kidney disease [9]official.
What speaks against it and what is unknown
Liraglutide lowers body weight, but the effect is modest and it does not work for everyone. According to the EMA the effect is modest, particularly in men [3]regulator.
Evidence against
- According to the EMA, about 30% of participants in the main studies did not complete them. With a more conservative analysis the weight loss was similar but smaller [3]regulator.
- Of those who had lost less than 5% at 12 weeks, 93.4% did not reach a 10% loss after one year [5]official.
- In the three-year SCALE continuation about half withdrew and were not followed up, so it does not show adults' weight after stopping [8]A. In the S-LiTE trial weight came back after liraglutide was stopped [10]A.
- According to the EMA, it is not clear whether the lower BMI in children and adolescents will translate into health improvement [3]regulator.
What the evidence does not support
- "Saxenda and Victoza are different substances": the active substance is the same liraglutide. Saxenda is authorised for weight management and Victoza for type 2 diabetes [3, 4]regulator.
- "Liraglutide often causes pancreatitis": for Saxenda, pancreatitis is classed as uncommon, affecting 1 to 10 users in 1,000 [5]official. In LEADER, confirmed acute pancreatitis occurred in 0.4% of the liraglutide group and 0.5% of the placebo group [9]official.
- "Saxenda eventually works for everyone if used long enough": according to the EMA, treatment is stopped if an adult has not lost at least 5% within 12 weeks [3]regulator.
- "Liraglutide bought online is the same as the pharmacy medicine": products that do not come through a pharmacy are not authorised medicines, and according to Fimea an unauthorised product may contain a different substance from the one on the label [6]regulator.
Liraglutide dosage in studies
Liraglutide has an approved dosage, set out in the summaries of product characteristics approved by the EMA [5, 9]official. Below are first the doses used in trials and then the product information dosing as stated. Neither is dosing advice: the prescriber decides the dose and any change to it.
| Study | Who | Dose and route | Duration |
|---|---|---|---|
| SCALE Obesity and Prediabetes (2015) | 3,731 adults without type 2 diabetes | 3.0 mg under the skin once a day | 56 weeks [1]A |
| SCALE, three-year continuation (2017) | adults with prediabetes | 3.0 mg under the skin once a day | 160 weeks [8]A |
| SCALE trials, dose escalation | participants in the weight management trials | dose raised to 3.0 mg | 4 weeks [5]official |
| LEADER (2016) | 9,340 people with type 2 diabetes | up to 1.8 mg once a day (compared with placebo) [5]official | median 3.8 years [2]A |
| Product | Who | Dose and route | Duration |
|---|---|---|---|
| Saxenda, escalation | weight management: adults, from 12 years, and 6 to 11 years | 0.6 mg, 1.2 mg, 1.8 mg and 2.4 mg under the skin once a day, one week each | 4 weeks [5]official |
| Saxenda, maintenance | same | 3.0 mg under the skin once a day (more than 3.0 mg not recommended) | review after 12 weeks: in adults stop if weight has not fallen by at least 5%; in adolescents and children if BMI has not fallen by at least 4% [5]official |
| Victoza, start | type 2 diabetes, adults and from 10 years | 0.6 mg under the skin once a day | at least one week [9]official |
| Victoza, maintenance | same | 1.2 mg, if needed 1.8 mg under the skin once a day (more than 1.8 mg not recommended) | increase to 1.8 mg after at least one week [9]official |
What the numbers do not tell you. These are trial and product information figures, not a recommendation for anyone. According to the product information, stopping treatment is considered if the next escalation step is not tolerated for two consecutive weeks [5]official. Dose page: Approved liraglutide dosing. Calculator page: dose calculator (it has no ready-made preset for liraglutide). Other substances: Dosing.
Saxenda vs Victoza: what is the difference?
The active substance is the same liraglutide, but the indication and the dose differ [3, 4]regulator [5, 9]official.
- Indication: Saxenda is authorised for weight management [3]regulator, Victoza for type 2 diabetes [4]regulator.
- Dose: according to the product information, the Saxenda maintenance dose is 3.0 mg a day [5]official, and Victoza no more than 1.8 mg a day [9]official.
- Who: Saxenda under set conditions also for children aged 6 to 11 and adolescents from 12 [3]regulator, Victoza for adults and from 10 years [4]regulator.
How liraglutide, semaglutide and tirzepatide differ: Weight-loss drugs (GLP-1), semaglutide and tirzepatide.
Liraglutide was the comparator in the phase 2 cagrilintide trial: cagrilintide vs liraglutide.
Is liraglutide legal in Finland?
Yes, as a prescription medicine. Liraglutide has a marketing authorisation in the EU [3, 4]regulator, and it is listed in Annex 1 of Fimea's medicines list [7]regulator.
- Prescription. Saxenda and Victoza are available only with a prescription [3, 4]regulator.
- Medicines list. Liraglutide is listed in Annex 1 of Fimea's medicines list (decision 230/2025) [7]regulator. Annex 1 substances are controlled as medicines in Finland, so liraglutide is a medicine, not a supplement or a chemical.
- Fimea warning, 29 June 2026. Fimea warned about injectable peptides sold online and on social media, including products marketed for weight management. According to Fimea, medicines should be bought only from legal pharmacies [6]regulator. Liraglutide products that do not come through a pharmacy are not authorised medicines.
- Import. Ordering medicines from outside the EU is covered on Peptides and the law in Finland. Bringing them back from travel: Travelling with peptides.
This is not legal advice. Disclaimer.
How is a liraglutide product assessed?
Liraglutide from a pharmacy has been manufactured, tested and supervised through the marketing authorisation process. According to Fimea, an unauthorised product bought online may contain a different substance from the one on the label, and in injectables impurities such as endotoxins can cause serious harm [6]regulator.
A seller's own certificate of analysis (COA) does not prove product quality by itself, and a "for research use only" label means the product is not intended for humans [6]regulator. More: How to read a COA and check a test result.
FAQ
Saxenda doses: what liraglutide dose did studies use?
The SCALE trial used 3.0 mg of liraglutide once a day [1]A, reached by raising the dose over four weeks [5]official. The prescriber decides the dose, and instructions are in the package leaflet. More: liraglutide dosage in studies.
Saxenda not working: what is known about liraglutide?
It does not work for everyone. According to the EMA, treatment is stopped if an adult has not lost at least 5% of body weight after 12 weeks on the maximum dose or the maximum tolerated dose, and the doctor reassesses the need to continue once a year [3]regulator. Of those who had lost less than 5% at 12 weeks, 93.4% did not reach a 10% loss after one year [5]official.
Saxenda pancreatitis: how common is it with liraglutide?
Uncommon. For Saxenda, pancreatitis is classed as an uncommon side effect [5]official. In LEADER, confirmed acute pancreatitis occurred in 0.4% with liraglutide and 0.5% with placebo [9]official. Severe and persistent abdominal pain that may reach the back, with nausea and vomiting, is a reason to contact a doctor straight away [5]official.
Stopping Saxenda: does the weight come back after liraglutide?
In trials, at least partly yes. In the Danish S-LiTE trial, adults who stopped liraglutide regained 6.0 kg more over the following year than those who stopped an exercise programme, and more of those who had combined exercise and liraglutide kept a weight loss of at least 10% [10]A. In a trial in adolescents, weight began to come back during 26 weeks of follow-up after treatment ended [5]official. Talk to your prescriber before stopping.
How much weight is lost on Saxenda?
In trials a mean of 8.4 kg over 56 weeks, against 2.8 kg with placebo [1]A. In the EMA pooled assessment the loss was 7.5%, against 2.3% with placebo [3]regulator. One person's experience does not show how the medicine works for others.
What do users themselves report about liraglutide?
In the Reddit accounts of 188 people we compiled (not research), 127 (68%) reported some benefit and 123 (65%) some harm. The accounts are self-selected and prove neither that it works nor that it is safe: Liraglutide user experiences.
Saxenda vs Victoza: what is the difference if both contain liraglutide?
The active substance is the same. Saxenda (liraglutide) is authorised for weight management [3]regulator and Victoza (liraglutide) for type 2 diabetes [4]regulator, and their approved doses differ [5, 9]official.
Liraglutide without a prescription: is it possible?
No. Saxenda and Victoza are available only with a prescription [3, 4]regulator. Fimea warns against buying injectable peptides online [6]regulator.
Read the research yourself: sources
Every source opens the original publication or the regulator's page. The level shows what the source itself reports.
- Pi-Sunyer X, et al. A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management (SCALE Obesity and Prediabetes). N Engl J Med. 2015;373(1):11-22. PMID 26132939 A
- Marso SP, et al. Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes (LEADER). N Engl J Med. 2016;375(4):311-322. PMID 27295427 A
- European Medicines Agency. Saxenda: EPAR summary for the public and authorisation details. EMA regulator
- European Medicines Agency. Victoza: EPAR medicine overview and authorisation details. EMA regulator
- European Medicines Agency. Saxenda: product information (summary of product characteristics and package leaflet). EMA (PDF) official
- Fimea. Fimea varoittaa: älä käytä verkosta ostettuja pistettäviä peptidejä / Fimea warns: do not use injectable peptides purchased online. 29 Jun 2026. Fimea regulator
- Finland. Lääkeluettelo (Fimea medicines list), 230/2025, annex 1. Finlex regulator
- le Roux CW, et al. 3 years of liraglutide versus placebo for type 2 diabetes risk reduction and weight management in individuals with prediabetes: a randomised, double-blind trial. Lancet. 2017;389(10077):1399-1409. PMID 28237263 A
- European Medicines Agency. Victoza: product information (summary of product characteristics). EMA (PDF) official
- Jensen SBK, et al. Healthy weight loss maintenance with exercise, GLP-1 receptor agonist, or both combined followed by one year without treatment: a post-treatment analysis of a randomised placebo-controlled trial. EClinicalMedicine. 2024;69:102475. PMID 38544798 A
- European Medicines Agency. Ablymico (liraglutide): EPAR medicine overview, hybrid medicine with reference medicine Saxenda, EU marketing authorisation 15 Jul 2026. Read 14 Oct 2026. EMA regulator
Research sources checked 12 Oct 2026. Regulator and registry sources checked 15 Sep to 13 Oct 2026.
Evidence levels: A = randomised human trial or meta-analysis · B = observational human study or case series · C = animal study · D = cell or laboratory study · E = not peer-reviewed · regulator = a regulator's assessment or decision, not research evidence. The marker official means official product information (summary of product characteristics or label); it is not research evidence. For a review, the level shows what kind of research the statement rests on. No level: statements that something has not been studied, reviews' interpretations, named hypotheses and the general rules in our certificate-of-analysis guide.
Content is general information about research, not medical advice. If you have symptoms, contact a healthcare professional.