Most brain aneurysms that haven't ruptured don't cause symptoms. This is especially true if they're small. Brain aneurysms may be found during imaging tests that are done for other conditions. However, a ruptured aneurysm is a very serious condition, typically causing a severe headache. And if an unruptured aneurysm presses against brain tissue or nerves, it may cause pain and other symptoms. Ruptured aneurysm A sudden, severe headache is the key symptom of a ruptured aneurysm. This headache is often described by people as the worst headache they've ever experienced. In addition to a severe headache, symptoms of a ruptured aneurysm can include: 
Nausea and vomiting
Stiff neck
Blurred or double vision
Sensitivity to light
Seizure
A drooping eyelid
Loss of consciousness
Confusion
 'Leaking' aneurysm In some cases, an aneurysm may leak a slight amount of blood. When this happens, a more severe rupture often follows. Leaks may happen days or weeks before a rupture. Leaking brain aneurysm symptoms may include: 
A sudden, extremely severe headache that may last several days and up to two weeks.
 Unruptured aneurysm An unruptured brain aneurysm may not have any symptoms, especially if it's small. However, a larger unruptured aneurysm may press on brain tissues and nerves. Symptoms of an unruptured brain aneurysm may include: 
Pain above and behind one eye.
A dilated pupil.
A change in vision or double vision.
Numbness of one side of the face.
