Norco is a prescription medication commonly used to relieve moderate to severe pain. It is a combination drug that contains hydrocodone, an opioid pain reliever, and acetaminophen, a non-opioid pain reducer. Together, these ingredients work to decrease pain signals in the brain and improve comfort after injuries, surgeries, or certain medical conditions. Because Norco contains an opioid, it is classified as a controlled substance and should only be used under a doctor’s supervision.