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What happens during a brain hemorrhage (bleeding in the brain)?

Photo of a man with a bad headache

The skull protects the brain, but it also limits the amount of available space: Bleeding inside the skull quickly increases the pressure on the brain tissue. This often causes serious complications. Possible symptoms of a brain hemorrhage (bleeding in the brain) include paralysis in certain parts of the body and speech problems.

Brain hemorrhages occur when blood vessels inside the skull are damaged, for instance due to a major head injury. Other causes include problems with blood clotting or damage to the blood vessels in the brain – due to high blood pressure or thickened and hardened artery walls (arteriosclerosis), for example. Sometimes, the bleeding is caused by a ruptured (burst) brain aneurysm. A brain aneurysm is a bulge in an artery in or near the brain.

There are different types of brain hemorrhages, depending on where the bleeding occurs:

  • Subarachnoid hemorrhage in the fluid-filled space surrounding the brain
  • Intracerebral hemorrhage within the brain tissue
  • Subdural hemorrhage between the two meninges (membranes covering the brain)
  • Epidural hemorrhage between the skull bone and these membranes

What is a subarachnoid hemorrhage?

This type of bleeding is often caused by a ruptured brain aneurysm: Here, blood flows into the fluid-filled space surrounding the brain (the subarachnoid space).

The blood can spread rapidly within this space, pushing against the whole brain and leading to a sudden increase in pressure within the skull. This means that even parts of the brain that aren't very close to the bleeding blood vessel can become damaged. The bleeding quickly results in a very bad headache. If the bleeding isn't treated, it can particularly cause people to lose consciousness or stop breathing. In rare cases, it leads to life-threatening heart rhythm problems.

If the bleeding results in brain damage, it can cause long-lasting or permanent problems in everyday life, or lead to the need for nursing care – for instance, because of speech problems or paralysis.

The illustration shows a subarachnoid hemorrhage, where blood flows into the fluid-filled space surrounding the brain.

What is an intracerebral hemorrhage?

If an artery in the brain bleeds directly within the brain tissue, it is known as an intracerebral hemorrhage. This is sometimes caused by high blood pressure. The blood that flows out presses against the brain tissue from the inside, pinching off other blood vessels there. The surrounding brain tissue dies as a result – like in a stroke. Because of this, it is also known as a hemorrhagic stroke.

Depending on the function of that part of the brain, people may have problems with their vision, speech, movement or sensations. Like subarachnoid hemorrhages, intracerebral hemorrhages can lead to life-threatening complications, especially if a lot of blood flows out.

The illustration shows an intracerebral hemorrhage in the middle of the brain, where blood from a cerebral artery leaks into the brain tissue.

Other types of bleeding

Blood can also leak into the small gaps between the two meninges (membranes covering the brain) or between the meninges and the skull bone: This kind of bleeding is often caused by a head injury – due to a fall, for example.

If veins in the brain are damaged as a result, bleeding may occur in the space between the two meninges known as the arachnoid mater and the dura mater. This is called a subdural hemorrhage, or subdural hematoma.

The illustration shows a subdural hemorrhage, with bleeding into the narrow spaces between the two membranes covering the brain (meninges).

If an artery that supplies the meninges with blood is injured, bleeding occurs between the skull and the dura mater. This is known as an epidural hemorrhage (epidural hematoma).

The illustration shows an epidural hemorrhage, where bleeding occurs in the space between the skull and the dura mater.

Subdural or epidural hemorrhages also put pressure on the brain and can cause serious damage as a result. They can lead to loss of consciousness and become life-threatening. Like other types of bleeding in the brain, they can result in permanent problems in daily life and the need for nursing care.

Etminan N, de Sousa DA, Tiseo C et al. European Stroke Organisation (ESO) guidelines on management of unruptured intracranial aneurysms. Eur Stroke J 2022; 7(3): V.

Hacke W. Neurologie. Berlin: Springer; 2016.

Lippert H. Lehrbuch Anatomie. Munich: Urban und Fischer; 2017.

Pschyrembel Online. 2026.

Steiner T, Juvela S, Unterberg A et al. European Stroke Organization guidelines for the management of intracranial aneurysms and subarachnoid haemorrhage. Cerebrovasc Dis 2013; 35(2): 93-112.

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. informedhealth.org can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

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What happens during a brain hemorrhage (bleeding in the brain)?

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Updated on April 27, 2026

Next planned update: 2029

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Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

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