An aneurysm occurs when a blood vessel in the brain begins to bulge due to weakness in the blood vessel wall. These enlarged vessels can leak, causing a rupture and bleeding in the brain. Once an aneurysm has burst or broken, it becomes life-threatening. Before the rupture, however, it may exist for years without detection, despite the fact that a growing aneurysm can cause a variety of symptoms.

Severe Headache

A severe and sudden headache is often the first sign of an impending rupture of an aneurysm in the brain. This kind of pain occurs when blood begins leaking from the aneurysm, otherwise known as a sentinel bleed. In most cases, an aneurysm will create a small leak. If the leak becomes severe, a rupture may follow. The pain of these headaches is incredibly intense and comes on suddenly. These two factors indicate the symptom is more than a normal headache and that the individual requires immediate medical assistance.

Eye Pain and Vision Problems

If a brain aneurysm is small, unruptured, and is not leaking, symptoms are often unnoticeable. Small aneurysms are most likely to be asymptomatic, while larger ones can press against the brain and nerve tissues of the eye, leading to pain behind and above the eye, a dilated pupil, blurred or double vision, or a visibly drooping eyelid. The pressure can also cause weakness or paralysis on one side of the face.

Neck Pain

In addition to a searing headache, another telltale sign of a pending aneurysm can be neck and shoulder pain. The nerves and muscles that lead up and around the head are all connected through the neck, so painful headaches can lead to tension and therefore pain in the neck, even if the headache pain is concentrated behind the eye. This neck pain can be associated with a tingling feeling traveling from the face into the neck.

Nausea and Vomiting

Nausea and vomiting can be symptomatic of a ruptured aneurysm, and will usually come on quickly and be followed by more severe signs. When an aneurysm ruptures, it increases pressure within the brain, and this can lead to nausea and vomiting. The vomiting is usually accompanied by other symptoms such as a severe headache and a stiff neck. Nausea and vomiting can be symptoms of a variety of health conditions, but when these symptoms are associated with a headache and neck stiffness, immediate medical care is needed.

Seizures

Abnormal electrical activity in the brain causes seizures. This brain activity determines the size, length, and severity of the seizure. Seizures can be so small that they may go unnoticed initially. More severe seizures can cause involuntary muscle spasms and convulsions, jaw lock, shaking, and fainting. They can come on suddenly. Seizures call for immediate medical attention, especially for those who have never experienced one before.

Confusion

A brain aneurysm can cause sudden confusion when the brain stops working at full capacity. This sensation can be disarming, particularly when it occurs unexpectedly and without explanation. People who feel inexplicably and suddenly confused should seek help immediately, as confusion is not always evident to anyone but the person experiencing it.

Fainting

Fainting or loss of consciousness is a sudden collapse of the body caused by decreased blood flow and lack of oxygen to the brain. When a person experiences an aneurysm, he or she may lose consciousness due to the amount of bleeding from the brain, which can also prompt a seizure. If the bleeding continues and is not immediately treated, coma can follow. Fainting can also follow intense pain, which can send the body and brain into shock.

Light Sensitivity

Sensitivity to light is called photophobia. The term describes pain or discomfort in the eyes upon exposure to light. Many conditions and events, such as migraines, can lead to this symptom. In the case of an aneurysm, sensitivity can increase as the aneurysm enlarges in size and may not be recognized as a symptom of an aneurysm initially.

Fatigue

Fatigue is subjective, which can make it difficult to pinpoint and serve as a diagnostic tool. Blood loss is one cause of fatigue. In the case of an aneurysm, the sudden onset of severe fatigue and weakness could be a sign that the blood vessel is leaking and nearing rupture. While rest can usually alleviate fatigue, if an aneurysm is the cause, extra sleep is unlikely to help.

Weakness

Weakness is different from tiredness or fatigue. It implies a lack of physical strength in the muscles more so than mental exhaustion. Weakness leaves the body requiring extra effort to move — effort it often cannot make. The symptom can also result from pain. When an aneurysm is to blame for weakness, the sensation may intensify over time or could come on suddenly.