Central nervous system cytokines and morphine analgesia. Morphine remains the drug of choice for the management of moderate-to-severe pain, however its clinical effectiveness is compromised by the fact that morphine's analgesic (pain reducing) efficacy becomes less effective the more it is administered.. This project will examine how analgesic tolerance develops from a completely new approach: Namely, how stimulation of the immune system within the central nervous system is a crucial factor in t ....Central nervous system cytokines and morphine analgesia. Morphine remains the drug of choice for the management of moderate-to-severe pain, however its clinical effectiveness is compromised by the fact that morphine's analgesic (pain reducing) efficacy becomes less effective the more it is administered.. This project will examine how analgesic tolerance develops from a completely new approach: Namely, how stimulation of the immune system within the central nervous system is a crucial factor in the development of tolerance. Modulation of analgesia by the immune system has not been systematically studied and provides a potentially fertile ground for the development of new techniques in the management of clinical pain.Read moreRead less