What the Saxenda® documents say about clotting
There is no venous thromboembolism, deep vein thrombosis or pulmonary embolism entry in the Saxenda® adult or teenage tables, in the EU frequency table or in the Canadian monograph, and none among the post-marketing reports listed in the US label. [1][2][3] For a medicine studied in more than 3,000 adults on active treatment, 29% of whom had a BMI above 40, that absence is informative, although trials of up to 56 weeks can miss rare events. [1]
| Topic | What it says | Source |
|---|---|---|
| Clot side effects (DVT, PE, VTE) | Not listed | US label 6.1 and 6.2; EU Table 4; Canadian 8 [1][2][3] |
| Warfarin and other coumarins | More frequent INR monitoring when liraglutide starts | EU 4.5; Canadian 9.4 [2][3] |
| Oral medicines in general | Slower stomach emptying may affect absorption; monitor | US label 7.1 [1] |
| Surgery and procedures | Tell providers beforehand that you take Saxenda® | US label 5.9; Canadian 7 [1][3] |
| Pregnancy | Stop Saxenda® once pregnancy is recognised | US label 8.1 [1] |
What the GLP-1 meta-analyses found
Two 2025 reviews pooled randomised trials of GLP-1 medicines, liraglutide among them. The first, with 39 trials and 70,499 people, found a non-significant upward trend for clots overall, a higher rate of deep vein thrombosis, about 25 extra cases per 10,000 person-years, concentrated in trials lasting longer than 18 months, and no change in pulmonary embolism. [4] When it split the results by medicine, only albiglutide showed a significant rise in overall clots; liraglutide did not. [4]
The second review, with 27 placebo-controlled trials and 84,003 people, found no significant difference in overall clots and a lower risk of pulmonary embolism with GLP-1 medicines. [5] The two analyses used different trial sets and methods, which is why their headlines differ. Neither was designed around Saxenda® or the 3 mg dose.
Evidence specific to liraglutide
In a 26-week randomised trial in 72 women with polycystic ovary syndrome, a condition linked with higher clot risk, liraglutide 1.8 mg caused about 5% weight loss and lowered some laboratory markers of clotting, with a trend towards better clot breakdown, though not significantly differently from placebo. [7] The authors called the direction encouraging but asked for larger studies.
A 2026 analysis of US adverse event reports from 2020 to 2025 found 1,618 clot reports with GLP-1 medicines and no excess overall compared with all other drugs; venous clots had the lowest reporting odds. Among the individual medicines, liraglutide showed higher reporting odds than the others. [6] Reporting databases cannot measure risk or prove cause.
Why the question comes up at all
- The people who take Saxenda® often carry other risk factors: obesity is one, and so are older age, smoking, cancer, a family history of clots and oestrogen-containing medicines. [8]
- Surgery and inactivity: clot risk is highest after major surgery, with the first three months carrying the most risk, and after long periods of sitting or bed rest. [10] The Saxenda® label separately asks you to tell providers before any planned procedure. [1]
- Pregnancy and the months after birth raise risk. [8] Saxenda® is stopped once a pregnancy is recognised. [1]
- Long trips: flights of more than four hours, especially with other risk factors, are a known setting for leg clots. [10]
If you take a blood thinner
Saxenda® slows stomach emptying, which can change how quickly medicines taken by mouth are absorbed. [1] For warfarin and similar coumarin medicines, which have a narrow safe range, the EU and Canadian documents say a relevant interaction cannot be excluded and ask for INR, the warfarin blood test, to be checked more often when liraglutide is started. [2][3] The EU leaflet tells patients to mention warfarin or other oral anticoagulants before starting. [2]
MedlinePlus notes that blood thinners need careful use, regular blood tests for some types, and a full list of your medicines and supplements for your provider; serious bleeding, such as nosebleeds or gum bleeding that will not stop, or a much heavier period, needs a call. [11] Vomiting or diarrhoea on Saxenda® can also make it harder to take tablets on schedule, which is worth raising with whoever manages your anticoagulant. [1]
Reducing your overall risk
MedlinePlus advises moving your legs often on long car or plane journeys and whenever you have to sit or lie still for long, taking blood thinners if they are prescribed, and not smoking. [8] NHLBI suggests asking your provider about a prevention plan before major surgery. [10] Those steps apply whether or not you take Saxenda®. Any decision to pause Saxenda® around surgery is your prescriber’s, together with the surgical team. [1]
Saxenda® is a registered trademark of Novo Nordisk A/S. PepLabo is not affiliated with or endorsed by Novo Nordisk.
When to get help
The signs and contact information below come from this article’s sourced guidance.
Emergency
- Sudden shortness of breath, chest pain that worsens with breathing, coughing up blood or fainting
Contact: Emergency services (911 / 112)
MedlinePlus [9]