A lumbar puncture is a test of the fluid around your spine and brain. This fluid is called cerebrospinal fluid (CSF). It provides protection and nutrition to the brain and nerve cells. CSF also helps to remove waste products from the brain.
The test is done to look for anything abnormal in the CSF. It may be done to help diagnose conditions such as:
The procedure may also be done to:
Problems from the procedure are rare, but all procedures have some risk. The doctor will review possible problems, like:
The doctor will need to know about any medicine you are taking or any allergies.
Local anesthesia will be used most often. It numbs just a small area.
You will likely lie on your side with your knees drawn up in front. Some punctures may be done while you sit on the edge of the bed. The site where the needle will be inserted will be cleaned. A needle will be inserted through the lower back and into the spinal canal. A sample of CSF will be taken through the needle.
The pressure of the CSF may be noted during the procedure. The needle may need to be repositioned if it is causing pain. It may take several minutes to collect the fluid that is needed. The needle will be removed. A dressing will be placed over the site.
You will lie down for 10 to 60 minutes. You will often be able to go home after the procedure. If you have a severe headache or need immediate treatment, you may need to stay longer.
About 30 to 45 minutes from setup to completion
A lumbar puncture can be uncomfortable. The anesthesia will sting when it is first injected.
Rest and self care will be needed for at least 24 hours.
Talk to your doctor if recovery is not going as expected or any of the following occurs:
If you think you have an emergency, call for medical help right away.
Family Doctor—American Academy of Family Physicians
National Institute of Neurological Disorders and Stroke
About Kids Health—The Hospital For Sick Children
Doherty CM, Forbes RB. Diagnostic Lumbar Puncture. Ulster Med J. 2014 May;83(2):93-102.
Lumbar puncture (LP). EBSCO DynaMed website. Available athttps://www.dynamed.com/procedure/lumbar-puncture-lp/. Updated March 27, 2019. Accessed March 14, 2019.
Lumbar puncture. Radiological Society of North America Patient website. Available at: https://www.radiologyinfo.org/en/info.cfm?pg=spinaltap. Updated April 30, 2018. Accessed March 14, 2019.
Last reviewed March 2019 by EBSCO Medical Review Board Rimas Lukas, MD Last Updated: 3/14/2019