Last updated: October 2026
CBD can occasionally cause palpitations, but it isn’t common at supplement doses. In studies, a large 600mg dose lowered blood pressure slightly and raised heart rate by a few beats a minute. More often, palpitations after CBD come from THC in a mislabelled product, caffeine, anxiety or a big first dose. Call 999 if chest pain or breathlessness occur too.
Below: what research shows about CBD and the heart, the common causes, what to do straight away, how to prevent it, and heart medicines.
CBD and the heart: what studies show
| Study | What it found |
|---|---|
| Single dose, 2017 (9 healthy men, 600mg CBD) | Resting systolic blood pressure fell by about 6mmHg; heart rate rose, by around 10 beats a minute during stress tests |
| Seven days, 2020 (26 healthy men, 600mg CBD a day) | Blood pressure fell after the first dose; the resting effect faded after a week, though lower blood pressure during stress persisted |
| THC (for comparison) | THC commonly causes a fast heart rate, and is a more likely culprit |
The heart rate rise is thought to be the body compensating for a small drop in blood pressure. These doses were 60 times the FSA’s 10mg a day figure, so effects at supplement doses are likely to be much smaller.
Common causes of palpitations after CBD
- THC in the product: UK testing has found measurable THC in many CBD products. THC raises heart rate.
- A big first dose, especially on an empty stomach.
- Caffeine: at high doses CBD slows how fast caffeine is cleared. See CBD and caffeine.
- Anxiety: worrying about a new product can cause a racing heart by itself.
- A drop in blood pressure, especially standing up quickly.
- Other causes that happen to coincide: alcohol, dehydration, nicotine, stress or a heart rhythm problem.
What to do if it happens
- Stop and don’t take any more.
- Sit or lie down and breathe slowly.
- Drink some water and avoid caffeine and alcohol.
- Note the product, dose and time, and check its lab report for THC.
- If it passes quickly, mention it to a pharmacist or GP before trying CBD again.
When palpitations need urgent help
The NHS advises: call 999 or go to A&E if palpitations don’t go away, or come with chest pain, shortness of breath, or feeling faint or fainting. See a GP if they keep coming back or are happening more often, last longer than a few minutes, or you have a heart condition.
How to prevent it
- Choose THC-free CBD with a batch lab report showing THC not detected. See how to read a lab report.
- Start low: around 10mg, with food. The FSA’s 10mg a day figure is precautionary advice rather than a legal limit, set while longer-term safety research continues. At Evopure we think it is a very cautious figure, and many adults use more. If you go above it, increase slowly, and check with your GP or pharmacist first if you take any medication.
- Separate from coffee or cut back caffeine.
- Try the evening, when you’re resting.
- Capsules give an exact dose. See CBD oil vs capsules.
CBD and heart medicines
CBD can affect how the liver breaks down some medicines, including some blood thinners, statins, heart rhythm and blood pressure medicines. Because it can also lower blood pressure, check with your GP or pharmacist before using CBD if you take any heart or blood pressure medicine. See can CBD interact with medication? and the grapefruit warning.
Related guides
- Palpitations can be a physical sign of anxiety. See anxiety symptoms.
- A sudden racing heart with fear can be a panic attack. See how to stop a panic attack.
- If worrying about palpitations is taking over, see health anxiety.
- Anxiety chest pain.
FAQs
Can CBD cause heart palpitations?
Occasionally. Large doses can raise heart rate slightly as blood pressure dips, but palpitations are more often due to THC, caffeine, anxiety or a big first dose.
Does CBD raise or lower heart rate?
In studies, 600mg of CBD lowered blood pressure a little and raised heart rate a few beats a minute. Effects at supplement doses are likely smaller.
Can CBD cause heart flutters?
Some people notice flutters, often with caffeine, anxiety or THC-containing products. Seek help if they come with chest pain, breathlessness or fainting.
Is CBD safe for people with heart conditions?
Check with your GP or cardiologist first. CBD can lower blood pressure and interact with some heart medicines.
Can CBD cause palpitations at night?
It can, but night-time palpitations are often linked to caffeine, alcohol, stress or poor sleep. If they keep happening, see a GP.
Should I stop CBD if I get palpitations?
Yes, stop and speak to a pharmacist or GP before trying again. Get urgent help if you have chest pain, breathlessness or fainting.
Sources
- Jadoon KA et al. A single dose of cannabidiol reduces blood pressure in healthy volunteers in a randomized crossover study. JCI Insight, 2017.
- Sultan SR et al. The effects of acute and sustained cannabidiol dosing for seven days on the haemodynamics in healthy men. Br J Clin Pharmacol, 2020.
- NHS. Heart palpitations.
- emc. Epidyolex: summary of product characteristics.
