NCIt definition : A semisynthetic hydrogenated codeine derivative and opioid agonist with analgesic
and antitussive effects. Hydrocodone primarily binds to and activates the mu-opioid
receptor in the central nervous system (CNS). This leads to analgesia, euphoria, respiratory
depression, miosis, decreased gastrointestinal motility, cough suppression and physical
dependence. Hydrocodone is converted to hydromorphone by the cytochrome P450 enzyme
CYP2D6.;