What is a subarachnoid hemorrhage?
A person with a subarachnoid hemorrhage has bleeding in the space between the brain and the lining that covers the brain, called the arachnoid. Causes of subarachnoid hemorrhage include an arteriovenous malformation, a cerebral aneurysm, and a head injury. About 1 out of 10,000 people develop a subarachnoid hemorrhage in the US each year.

What are the symptoms of subarachnoid hemorrhage?
The most common symptom of a subarachnoid hemorrhage is the sudden onset of a severe headache. Usually, the headache is the worst headache a person has ever experienced. Additional symptoms of a subarachnoid hemorrhage include nausea, vomiting, neck stiffness, fainting, or excessive sleepiness. Symptoms of severe subarachnoid hemorrhage include sudden arm or leg weakness, facial weakness, difficulty speaking, difficulty swallowing, difficulty walking, confusion, or coma.

How does the doctor treat a subarachnoid hemorrhage?
Treatment for a subarachnoid hemorrhage may include intravenous fluids, oxygen therapy, medications, or surgery.