Dizziness in the three documents
All three regulators list dizziness for Saxenda®, and the EU places it in its common class. [1][2][3] The US and Canadian adult figures come from five placebo-controlled trials, the teen figures from one 56-week trial. [1][3]
| Document and group | Saxenda® | Placebo | Note |
|---|---|---|---|
| US label, Table 2, adults [1] | 6.9% | 5.0% | Mostly in the first 12 weeks |
| Canadian monograph, Table 3, adults [3] | 233 of 3,384 (6.9%) | 97 of 1,941 (5.0%) | Same adult pool |
| US label, Table 3, ages 12–17 [1] | 10.4% | 3.2% | One trial, 125 vs 126 teens |
| EU SmPC, Table 4 and section 4.7 [2] | Common | — | Mainly first 3 months; care with driving |
A small gap in adults, a wider one in teens
In adults, dizziness was only about two points above placebo, so many dizzy spells in the trials had ordinary causes. [1] In teenagers the difference was about seven points, and dizziness was one of the more frequent reactions in that trial. [1] Teens on Saxenda® also had more low blood sugar, which may explain part of it, though the label does not draw that link. [1]
Timing is consistent across the documents. The US and Canadian labels say dizziness, fatigue, weakness, malaise and taste change were mainly reported within the first 12 weeks and often together with digestive effects, and that most were mild to moderate and short-lived. [1][3] The EU leaflet says dizziness may be felt mainly during the first three months. [2]
Four label effects that can make you dizzy
- Low blood sugar. The Medication Guide lists dizziness or light-headedness, together with sweating, shakiness, hunger and a fast heartbeat. The risk is higher for adults with type 2 diabetes on insulin or a sulfonylurea and for teenagers. [1]
- Fluid loss. Vomiting and diarrhoea can dehydrate you, and MedlinePlus lists dizziness among signs of severe dehydration; the label links dehydration on liraglutide to kidney injury. [1][7]
- Lower blood pressure. In the main trial, systolic pressure fell by 4.3 mmHg on Saxenda® and 1.5 mmHg on placebo, and events of low blood pressure, including drops on standing, were reported by 1.1% against 0.5%. In four people on Saxenda®, systolic pressure dropped below 80 mmHg. [1]
- Heart rhythm. Resting heart rate rose by 2 to 3 beats per minute on average, tachycardia was reported by 0.6% against 0.1%, and 0.3% had a heart conduction change against none on placebo. [1] The Canadian monograph also describes a slight lengthening of the PR interval on an ECG. [3]
What a reporting database adds
A 2025 analysis of nearly two decades of the US FDA adverse event reporting system looked at neurological reports for six GLP-1 medicines, liraglutide among them. Dizziness and presyncope, the feeling of being about to faint, were among the signals, and almost half of these reports came within 30 days of starting treatment. [4]
Such databases depend on voluntary reports. They can flag a pattern worth watching but cannot show how often dizziness happens or prove that the medicine caused it. [4] The trial figures above remain the better guide to frequency.
Other reasons for feeling dizzy
MedlinePlus separates light-headedness, a feeling you might faint, from vertigo, a spinning sensation. Light-headedness comes from too little blood reaching the brain, for example after standing quickly, with dehydration, a sudden fall in blood pressure, low blood sugar, flu or a cold, or from medicines that lower blood pressure. [5] If you take blood pressure tablets, the modest fall in pressure on Saxenda® is worth mentioning to your prescriber. [1][5]
Vertigo is more often an inner ear problem such as benign positional vertigo, labyrinthitis or Ménière disease. [5] Serious causes such as heart rhythm problems, stroke or internal bleeding usually bring other warning signs, including chest pain, a racing heart, slurred speech or vision change. [5]
Staying safe while it lasts
For light-headedness on standing, MedlinePlus suggests avoiding sudden changes in posture, getting up slowly and sitting for a moment before standing, and having something to hold on to. For vertigo, it suggests keeping still during attacks, avoiding sudden movements and increasing activity gradually. [5]
The EU summary asks for caution with driving or machines when dizzy, and the Canadian leaflet says not to drive if you feel dizzy. [2][3] If you are at risk of low blood sugar, your provider should explain how to recognise and treat it; the Medication Guide also asks you to check your blood sugar before and during Saxenda® if you have type 2 diabetes. [1] Drinking fluids to avoid dehydration is part of the same guidance. [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
| Sign | Who to contact | How fast | Source |
|---|---|---|---|
| Dizziness with chest pain, an irregular or racing heartbeat, shortness of breath, weakness in an arm or leg, or a change in speech or vision | Emergency number now | Emergency | MedlinePlus [5] |
| Fainting, or dizziness with swelling of the face or throat and trouble breathing | Stop Saxenda® and call your emergency number | Emergency | Medication Guide [1]; MedlinePlus [5] |
| Dizziness with sweating, shakiness or confusion if you take insulin or a sulfonylurea, or are a teen on Saxenda® | Check blood sugar and treat as you were shown; contact your care team | Today | Medication Guide [1]; MedlinePlus [6] |
| Dizziness with trouble keeping fluids down, or very little urine | Your provider the same day; seek urgent care if severe | Today | MedlinePlus [5][7] |
| A racing or pounding heart at rest lasting several minutes | Your prescriber | Today | Medication Guide [1] |
| Dizziness for the first time, new or worse dizziness, or dizziness after taking a medicine | Your doctor | At your next appointment | MedlinePlus [5] |
