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.

Lumbar Puncture Method
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Reasons for Procedure

The test is done to look for anything abnormal in the CSF. It may be done to help diagnose conditions such as:

  • Brain infection, or infection of the layers around the brain
  • Multiple sclerosis (MS)
  • Any disorder affecting the nervous system
  • Certain types of cancer
  • Bleeding in the brain or spinal cord
  • Excess CSF in the brain

The procedure may also be done to:

  • Deliver dye for imaging studies
  • Drain CSF to lower pressure within the brain
  • Give medicine directly to the spine, such as chemotherapy , antibiotics, and anesthesia

Possible Complications

Problems from the procedure are rare, but all procedures have some risk. The doctor will review possible problems, like:

  • Headache
  • Backache
  • Bleeding, which can compress the nerve roots or spinal cord
  • Pain or abnormal burning, pricking, or tingling sensations in legs
  • Allergic reaction to anesthetic
  • Infection

What to Expect

Prior to Procedure

Early tests including blood work, CT scan or MRI scan may be reviewed. You may be asked not to eat or drink anything after midnight the night before.

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.

Description of Procedure

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.

Immediately After Procedure

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.

How Long Will It Take?

About 30 to 45 minutes from setup to completion

Will It Hurt?

A lumbar puncture can be uncomfortable. The anesthesia will sting when it is first injected.

Post-procedure Care

Rest and self care will be needed for at least 24 hours.

Call Your Doctor

Talk to your doctor if recovery is not going as expected or any of the following occurs:

  • Severe headache or headache lasting for more than 24 hours
  • Nausea or vomiting
  • Signs of infection, including fever and chills
  • Redness, swelling, increasing pain, bleeding, or discharge from the lumbar puncture site
  • Numbness, tingling, or pain in your lower back or legs
  • Weakness in your lower legs or difficulty walking
  • Problems passing or controlling urine or stool
  • A stiff neck
  • Pain is not controlled with the medicine that was given

If you think you have an emergency, call for medical help right away.

Revision Information

  • Reviewer: EBSCO Medical Review Board Rimas Lukas, MD
  • Review Date: 03/2019 -
  • Update Date: 03/14/2019 -