Drug abuse, particularly the use of cocaine.Some of these risk factors develop over time, while others are present at birth. They're also more common in women than in men. Brain aneurysms are more common in adults than in children. Risk factorsĪ number of factors can contribute to weakness in an artery wall and increase the risk of a brain aneurysm or aneurysm rupture. The causes of most brain aneurysm are unknown, but a range of factors may increase your risk. Request an Appointment at Mayo Clinic Causes Aneurysms often form at forks or branches in arteries because those areas of the vessels are weaker.Īlthough aneurysms can appear anywhere in the brain, they are most common in arteries at the base of the brain. If you're with someone who complains of a sudden, severe headache or who loses consciousness or has a seizure, call 911 or your local emergency number.īrain aneurysms develop as a result of thinning artery walls.
Seek immediate medical attention if you develop a: However, a larger unruptured aneurysm may press on brain tissues and nerves, possibly causing: Unruptured aneurysmĪn unruptured brain aneurysm may produce no symptoms, particularly if it's small. This leaking may cause only a sudden, extremely severe headache.Ī more severe rupture often follows leaking. In some cases, an aneurysm may leak a slight amount of blood. In addition to a severe headache, common signs and symptoms of a ruptured aneurysm include: This headache is often described as the "worst headache" ever experienced. A sudden, severe headache is the key symptom of a ruptured aneurysm.