Norco 5-325 mg is a prescription drug used to treat moderate to fairly severe pain. Acetaminophen (325 mg) and hydrocodone bitartrate (5 mg) are its two active components. Acetaminophen is a non-opioid pain reliever and fever reducer that improves overall pain control, whereas hydrocodone is an opioid analgesic that acts by altering how the brain and nervous system react to pain.