Cyprodime is an opioid antagonist from the morphinan family of drugs.
Cyprodime is a selective opioid antagonist which blocks the ü-opioid receptor, but without affecting the ô-opioid or ú-opioid receptors. This makes it useful for scientific research as it allows the ü-opioid receptor to be selectively deactivated so that the actions of the ô and ú receptors can be studied separately, in contrast to better known opioid antagonists such as naloxone which block all three opioid receptor subtypes.