Lumbar puncture

What is a lumbar puncture?

A lumbar puncture, also known as a spinal tap, is a procedure in which your physician removes cerebrospinal fluid from the subarachnoid space in your spine, using a thin, hollow needle. Cerebrospinal fluid is the fluid surrounding the brain and the spinal cord.

There are many reasons why your physician may want to you to have a lumbar puncture. The cerebrospinal fluid can be analyzed for infection, cancer, bleeding, or heightened intracranial pressure. Your physician can tell you why you need to have a lumbar puncture. 

What to expect


You do not need to make preparations for your lumbar puncture. You can eat and drink as usual before the procedure. Please notify your physician if you take blood thinners. 

Diagnostic procedure

You will be lying on your side or sitting on the edge of the bed during the procedure, with your back as curved as possible. Your physician will start by disinfecting the skin, after which the needle will enter your body. Once enough fluid has been collected, your physician will remove the needle. The procedure will take approximately 15 to 30 minutes. 

Side effects and complications

Complications after a lumbar puncture are rare. Your physician may hit a nerve when inserting the needle. You will feel an electric shock or pain wave going through your leg. This sensation may hurt, but will not cause permanent nerve damage. Most people don’t feel the actual tapping once the needle is positioned correctly. One in twenty people will experience headaches after the procedure as a result of cerebrospinal fluid leaking from the hole in the back. These headaches increase when you get up and disappear when lying down. 


If you experience headaches after the procedure, please make sure you drink plenty of fluids. Especially caffeinated drinks (coffee or cola) can offer some pain relief. Paracetamol can help as well. Please take plenty of rest, and contact your neurologist if your headaches persist for longer than two days, or if you are experiencing a fever (with or without headaches).