Morphine's immunoregulatory actions are not shared by fentanyl

Fentanyl is a commonly used narcotic agent in anesthesia. It has strong analgesic properties which it shares with morphine. Unlike morphine, it does not possess the ability to bind to the μ₃ receptor, and therefore does not have the ability to influence nitric oxide release as measured amperometrically. Cell adhesion also is not influenced. As a result, it also lacks the ability to downregulate the inflammatory response associated with surgery, especially cardiopulmonary bypass.