Epidural administration (from Ancient Greek ἐπί, "upon" + dura mater) is a method of medication administration in which a medicine is injected into the epidural space around the spinal cord. The epidural route is used by physicians and nurse anesthetists to administer local anesthetic agents, analgesics, diagnostic medicines such as radiocontrast agents, and other medicines such as glucocorticoids. Epidural administration involves the placement of a catheter into the epidural space, which may remain in place for the duration of the treatment. The technique of intentional epidural administration of medication was first described in 1921 by the Spanish Aragonese military surgeon Fidel Pagés.
Epidural anaesthesia causes a loss of sensation, including pain, by blocking the transmission of signals through nerve fibres in or near the spinal cord. For this reason, epidurals are commonly used for pain control during childbirth and surgery, for which the technique is considered safe and effective, and is considered more effective and safer than giving pain medication by mouth or through an intravenous line. An epidural injection may also be used to administer steroids for the treatment of inflammatory conditions of the spinal cord. It is not recommended for people with severe bleeding disorders, low platelet counts, or infections near the intended injection site. Severe complications from epidural administration are rare, but can include problems resulting from improper administration, as well as adverse effects from medicine. The most common complications of epidural injections include bleeding problems, headaches, and inadequate pain control. Epidural analgesia during childbirth may also impact the mother's ability to move during labor. Very large doses of anesthetics or analgesics may result in respiratory depression.