RT Book, Section A1 Stringer, Janet L. SR Print(0) ID 1142821301 T1 Narcotics (Opiates) T2 Basic Concepts in Pharmacology: What You Need to Know for Each Drug Class, 5e YR 2017 FD 2017 PB McGraw-Hill Education PP New York, NY SN 9781259861079 LK accessmedicine.mhmedical.com/content.aspx?aid=1142821301 RD 2024/03/28 AB The word narcotics (or opiates) refers to drugs that act on specific receptors in the central nervous system (CNS) to reduce perception of pain. In general, they do not eliminate pain, but the patient is not as bothered by the pain. They act on three major classes of receptors in the CNS, called opioid receptors and designated mu (μ), kappa (κ), and delta (δ). Most of the actions of the narcotic analgesics are mediated by the μ receptor. Some actions are mediated through the κ and δ receptors.