Norco is a brand name for a combination medication that contains hydrocodone and acetaminophen. Hydrocodone is an opioid analgesic, similar to tramadol, and acetaminophen is a non-opioid pain reliever and fever reducer. Norco is typically prescribed to relieve moderate to severe pain. Hydrocodone, the opioid component of Norco, works by binding to opioid receptors in the brain and spinal cord, reducing the transmission of pain signals. Acetaminophen, the non-opioid component, helps to enhance the pain-relieving effects of hydrocodone and may also have its own mild pain-relieving and fever-reducing properties.