The epidural space is a common route for the administration of medications for analgesia, diagnosis of certain pain conditions, and procedural anesthesia. Medications are administered near the nerve roots responsible for the transmission of the signals intending to be blocked, i.e. sympathetic, sensory, or motor. Medication preparations are often isobaric and will follow gravity to affect other nearby levels. Medications from the epidural space have some vascular uptake as well as diffusion through the dura into nerve roots and the cerebrospinal fluid (CSF) to produce a wide range of effects. Complications from epidural medication administration fall into two categories. The first are complications related to the placement or misplacement of the needle and/or catheter. The second group of complications relates to the medications used.