This module walks you step-by-step through the entire pain pathway—from nociceptor activation in the periphery to cortical perception—so you can connect mechanism to management. You’ll unpack transduction, transmission, modulation, and perception, then layer on the roles of key neurotransmitters and receptors. Finally, you’ll tie it all together with a practical review of major pharmacologic options (NSAIDs, opioids, local anesthetics, steroids, acetaminophen, alpha-2 agonists, ketamine, antidepressants, and gabapentinoids), focusing on how each class interacts with the pain pathway and how to combine them for smarter, opioid-sparing clinical pain management.