Intrathecal route of drug delivery can save lives or improve quality of life.

In our final science article for 2012 on pharmaceutics, Kalliopi Dodou takes a look at the less commonly used intrathecal route of drug delivery

Intrathecal and epidural drug delivery comprise the intraspinal routes of drug administration. Each route delivers drug to the cerebrospinal fluid (CSF). Intrathecal delivery involves the direct injection of the drug into the CSF within the intrathecal space of the spinal column, whereas drugs injected in the epidural space have to cross the dura membrane in order to reach the CSF. As such, epidurally administered drugs can also reach the systemic circulation whereas intrathecally administered drugs are confined within the CSF circulating in the spinal column and the brain ventricles.1

Intraspinal drug delivery emerged in the 1970s when the presence of opioid receptors in the spinal cord was discovered and has since been exploited for the treatment of persistent pain in patients who do not respond to or experience serious side effects to other analgesic formulations. The intrathecal route allows direct drug administration to the CSF by circumventing the blood-brain barrier. It therefore allows delivery of smaller drug doses and the occurrence of side effects is reduced compared with systemic routes of drug administration (eg, oral, intravenous and epidural).