Hydrocodone and acetaminophen combination is used to relieve moderate to moderately severe pain. Acetaminophen is used to relieve pain and reduce fever in patients. It does not become habit-forming when taken for a long time.But acetaminophen may cause other unwanted effects when taken in large doses, including liver damage. Hydrocodone belongs to the group of medicines called narcotic analgesics (pain medicines).It acts on the central nervous system (CNS) to relieve pain, and stops or prevents cough. When hydrocodone is used for a long time, it may become habit-forming, causing mental or physical dependence.ydrocodone and acetaminophen combination is used to relieve moderate to moderately severe pain. Acetaminophen is used to relieve pain and reduce fever in patients. It does not become habit-forming when taken for a long time.