Hydrocodone: An opioid analgesic (narcotic) used to relieve moderate to severe pain. It works by binding to opioid receptors in the brain and spinal cord, reducing the perception of pain.Acetaminophen (325 mg): A less potent pain reliever that increases the effects of hydrocodone. It is also used to reduce fever.https://www.cureus.com/users/675092-health-service-at-cosmodix