<unk>  is a analgesic opioid that is FDA approved for the {{{indicationType}}} of analgesia in labor, epidural; adjunct,  general anesthesia.   Common adverse reactions include cardiovascular: bradyarrhythmia (3% to 9% ), hypotension (3% to 9% ), dermatologic: pruritus (25% ), gastrointestinal: nausea (3% to 9% ), vomiting (3% to 9% ), musculoskeletal: muscle rigidity, chest wall (3% to 9% ), neurologic: somnolence (3% to 9% ).
Sufentanil
Fentanyl 
Mirfentanil
Meperidine 
Normorphine
Nalorphine
Remifentanil
Alfentanil