by EBSCO Medical Review Board
(Water on the Brain)


Hydrocephalus is a buildup of cerebrospinal fluid (CSF) in the brain. This fluid surrounds the spinal cord and the brain. Too much of this fluid puts pressure on the brain.

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A person can be born with this problem or get it after an injury or illness.

Hydrocephalus can be caused by:

  • The brain being unable to absorb fluid due to things like bleeding or infection
  • A blockage that stops fluid from draining, such as tumors, injuries, and cysts
  • The body making too much fluid

Risk Factors

Things that may raise the risk of this problem are:

  • Adults who have:
    • Tumors
    • Brain infections or bleeding
    • Brain injuries
  • Babies who:
    • Are born very early
    • Have structural problems in the brain, spine, or spinal cord
    • Have bleeding in the brain
    • Have brain cysts
    • Are born to mothers who had infections during pregnancy, such as mumps


Symptoms may be mild at first and then get worse as pressure on the brain increases.

Problems in adults may be:

  • Headache
  • Nausea and vomiting
  • Eyesight problems, such as double vision
  • Problems walking
  • Confusion
  • Problems with urine control
  • Memory problems
  • Tremors
  • Problems swallowing
  • Loss of consciousness

Problems in babies may be:

  • Feeding problems
  • Slow development
  • Fussiness
  • Vomiting
  • Breathing that stops briefly during sleep
  • Loss of consciousness


The doctor will ask about your symptoms and health history. A physical exam will be done.

Images of the brain may be taken. This can be done with:

CSF may be tested in adults. This can be done with a lumbar puncture.


The goal of treatment is to ease pressure on the brain. Choices are:

  • Medicine to stop the body from making too much CSF and to ease swelling
  • Placing a shunt to let the excess fluid drain into another place in the body, often the belly
  • Making a hole in the brain to allow CSF to flow out
  • Removing anything that is blocking CSF flow, such as a tumor


There are no current guidelines to prevent this problem in adults. Getting regular prenatal care may help prevent it in infants.


National Hydrocephalus Foundation 

National Institute of Neurological Disorders and Stroke 


Health Canada 

Spina Bifida and Hydrocephalus Association of Canada 


Hamilton MG. Treatment of hydrocephalus in adults. Semin Pediatr Neurol. 2009 Mar;16(1):34-41.

Hydrocephalus in adults. EBSCO DynaMed website. Available at: Accessed January 25, 2021.

Hydrocephalus in children. EBSCO DynaMed website. Available at: Accessed January 25, 2021.

Hydrocephalus fact sheet. National Institute of Neurological Disorders and Stroke website. Available at: Accessed January 25, 2021.

Revision Information

  • Reviewer: EBSCO Medical Review Board Rimas Lukas, MD
  • Review Date: 12/2020
  • Update Date: 01/25/2021