A brain aneurysm is often called a "silent killer" for good reason. Many people live with unruptured aneurysms for years without knowing it. But when an aneurysm leaks or ruptures, it becomes a life-threatening emergency where every minute counts.

The challenge? The symptoms can be subtle—or sudden and severe. Knowing what to look for could save your life or the life of someone you love.

Important note: This information is for educational purposes. If you suspect a brain aneurysm, call emergency services immediately.

What Is a Brain Aneurysm?

A brain aneurysm is a weak or thin spot on a blood vessel in the brain that balloons out and fills with blood. Think of it like a weak spot on a balloon that bulges outward. If it ruptures, it causes bleeding in the brain—a hemorrhagic stroke that can lead to brain damage, disability, or death.

Two types of symptoms to know:

Unruptured aneurysm: May cause no symptoms or mild symptoms if it presses on nearby structures
Ruptured aneurysm: Causes sudden, severe symptoms that require immediate medical attention

Signs of an Unruptured Aneurysm (Before Rupture)

Many unruptured aneurysms cause no symptoms at all. But if they grow large enough to press on surrounding nerves or brain tissue, you might experience: