Which medication is NOT classified as a non-opioid analgesic?

Codeine is classified as an opioid analgesic, which distinguishes it from the other medications listed that are considered non-opioid analgesics. Opioid analgesics, such as codeine, interact with specific receptors in the brain and spinal cord to alter pain perception and can lead to physical dependence or addiction. In contrast, non-opioid analgesics like acetaminophen, naproxen, and ibuprofen work through different mechanisms, typically involving the inhibition of enzymes like cyclooxygenase (COX), which are involved in pain and inflammation pathways. By understanding these classifications, it is clear why codeine does not belong in the same category as the other three medications.