In most cases, an unruptured brain aneurysm will cause no symptoms unless it becomes big or begins to press against tissues or nerves inside the brain.

Symptoms of an unruptured brain aneurysm may include:

• visual disturbances, such as loss of vision or double vision
• difficulties moving one of your eyes
• pain on one side of your face or around your eye
• inability to move some of your facial muscles; usually only one side of your face is affected
• headaches
• seizures (fits)

If you do experience symptoms of a brain aneurysm, it's normally recommended that the aneurysm is treated as soon as possible.

Ruptured brain aneurysm

Symptoms of a ruptured brain aneurysm usually begin with a sudden and severe headache. It's been likened to being hit on the head, resulting in a blinding pain that's unlike anything ever experienced before.

Other symptoms include:

• stiff neck
• feeling sick
• being sick
• slurred speech
• sensitivity to light
• blurred or double vision
• mental confusion
• loss of consciousness

Medical emergency

A ruptured brain aneurysm is a medical emergency. If you suspect that you or someone in your care has had a ruptured brain aneurysm, call 999 immediately and ask for an ambulance.

Aneurysm

An aneurysm is a blood-filled sac that forms in a weakened part of a blood vessel.

Blood

Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.

Brain

The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.

Haematoma

Haematoma is a collection of blood in the tissues from a leaking blood vessel, which causes bruising.

Nausea

Nausea is when you feel like you are going to be sick.

Pain

Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.

Ruptures

A rupture is a break or tear in an organ or tissue.

Spine

The spine supports the skeleton, and surrounds and protects the delicate spinal cord and nerves. It is made up of 33 bones called the vertebrae.

Tissue

Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.  

Vomiting

Vomiting is when you bring up the contents of your stomach through your mouth.