An epidural blood patch is an injection of your blood into the epidural space. The epidural space is not an injection into the spinal cord itself. The spinal cord and spinal nerves are in a “sack” containing clear fluid (cerebrospinal fluid). The area outside this “sack” is called the epidural space. There are certain conditions under which patients will have had injections in the spinal column. Examples include an epidural during labor, a diagnostic spinal tap, a therapeutic spinal injection, etc. A small number of patients will experience a severe headache after the procedure, usually worse with standing and better when lying down. This is due to a persistent leak of spinal fluid into the epidural space. Although the headache itself is harmless, it can be very severe and very debilitating. Your doctor may ask you to come to our pain clinic for an “epidural blood patch”. The fluoroscopically guided injection of a freshly drawn sample of your own blood into the epidural space “plugs the leak” and the headache goes away.