ABSTRACT
The intrathecal and epidural administration of narcotics has become more prevalent in children. The administration of narcotics via the epidural or intrathecal route is performed in order to interrupt the pain transmission pathways of the spinal cord. The plasma protein binding of narcotics varies in extent and firmness in proportion to their lipid solubility. Narcotics are distributed by the blood to all the tissues and organs of the body. Both morphine-3-glucuronide and morphine-6-glucuronide are able to produce narcotic effects when they are injected directly into the central nervous system. Morphine-6-glucuronide is a minor metabolite in man under normal circumstances, but it has been reported to produce prolonged analgesic effects in animals when injected by various routes. After epidural morphine, the systemic uptake of drug from the epidural space may contribute significantly to the analgesic effect produced and to the occurrence of early side effects.
