ABSTRACT
Spinal administration refers to the delivery of drugs to the intrathecal or epidural space. The principle of spinal administration is to deliver drugs directly to the intrathecal or epidural space so that therapeutic concentrations can be achieved at the dorsal horn of the spinal cord, which cannot be achieved by systemic administration or only with extremely high systemic doses. Spinal administration can therefore be extremely effective in terms of analgesia and further, it can overcome unwanted motor, sensory, and autonomic effects from the systemic administration of what are inevitably larger doses of drugs. The drugs most commonly used for spinal administration are opioids. Spinal administration can be the route of delivery of other drugs and can enable patients to be exposed to drugs that are unstable by nonspinal routes of administration. Other drugs which are delivered by spinal administration are local anesthetics, clonidine, and more recently ziconotide.
