HEALTH CONDITION

Brain aneurysm

A brain aneurysm is a swelling in a blood vessel in your brain. If the aneurysm bursts it can cause a bleed on your brain, but this is rare.

Symptoms of a brain aneurysm

Most brain aneurysms are small and do not cause symptoms. They're often found during a test for another condition. If you have a larger aneurysm, you may get symptoms such as: a headache pain above or around your eye changes in your vision, such as double vision dizziness and balance problems numbness or weakness on 1 side of your face difficulty concentrating and speaking problems with your short-term memory If a brain aneurysm bursts, it can cause a bleed on your brain called a subarachnoid haemorrhage . The main symptom is a sudden, severe headache that's sometimes described as a "thunderclap headache".

Treatment for a brain aneurysm

Treatment is not usually needed for small brain aneurysms that are not causing symptoms. This is because they often do not get bigger and have a low risk of bursting. You may just need regular follow-up scans to check if it’s getting bigger. Brain aneurysm surgery If there’s a risk of the aneurysm bursting, or if it’s already burst, surgery will usually be needed. The 2 main types of surgery are: surgical clipping – where a small metal clip is attached to the blood vessel in the brain to stop blood flowing into the aneurysm endovascular surgery – where a coil or small piece of wire mesh is put inside the aneurysm to slow the flow of blood into it and help a blood clot to form If possible, your surgeon will talk to you about the procedure they feel is most suitable for you and discuss any risks involved. General anaesthetic is used for both surgical clipping and endovascular surgery, so you’ll be asleep and unable to feel any pain or discomfort during the procedure.

Causes of a brain aneurysm

It's not always clear what causes brain aneurysms. But things that increase your chances of getting a brain aneurysm include: smoking high blood pressure having a close relative who has had a brain aneurysm an injury to a blood vessel in your brain taking drugs, such as cocaine having certain genetic conditions, such as autosomal dominant polycystic kidney disease (ADPKD) or Ehlers-Danlos syndrome

Things you can do to help if you have a brain aneurysm

If you have a brain aneurysm there are some things you can do to reduce the risk of it getting bigger and bursting. Do stop smoking if you smoke keep your blood pressure at a healthy level – you can get your blood pressure checked at a pharmacy or GP surgery make healthy lifestyle changes, such as eating a balanced diet , exercising regularly and losing weight if you’re overweight Don’t do not drink too much alcohol do not take illegal drugs Important: Driving You may not be allowed to drive if you have a brain aneurysm. Your doctor will be able to advise you about whether it’s safe for you to drive and if you need to tell the DVLA.

Help and support for a brain aneurysm

Finding out you have a brain aneurysm can be scary and worrying. As well as getting help and advice from your doctor, you may find it helpful to talk to other people with the condition, either at a local support group or online. Headway Information, help and support for anyone affected by brain injury. Website: www.headway.org.uk/ Helpline: 0808 800 2244 Headway: online communities Brain and Spine Foundation Information and support for anyone affected by brain conditions, including brain aneurysm. Website: www.brainandspine.org.uk Helpline: 0808 808 1000 Brain and Spine Foundation: join a support group

Source: NHS, last reviewed 09 October 2025. Contains public sector information licensed under the Open Government Licence v3.0.

This page is general information and is not medical advice. It does not replace a registered doctor, and it is not a prescription or a recommendation to use any medicine or test. Prices are listed prices and may change. Always follow the advice of your doctor or pharmacist.