RT Book, Section A1 FUDIN, JEFFREY A1 PERKINS, RUTH J. A1 LIPMAN, ARTHUR G. A2 Cohen, Henry SR Print(0) ID 1112258274 T1 Opioids T2 Casebook in Clinical Pharmacokinetics and Drug Dosing YR 2015 FD 2015 PB McGraw-Hill Education PP New York, NY SN 9780071628358 LK accesspharmacy.mhmedical.com/content.aspx?aid=1112258274 RD 2024/10/14 AB Opioids are among the oldest documented medications used by humans. All opioids are derivatives of pharmacologically active alkaloids from the milky exudate of the opium poppy. These drugs act by binding at opioid receptors found in the CNS, the colon, and to a lesser extent, the periphery. Mu and kappa opioid receptors have clinical utility and delta opioid receptors offer promise, but no delta agonist has been found acceptable for human use to date. However, new work with biased legends offers promise of a possible future delta opioid agonist analgesic. Most clinically useful opioids are mu agonists that also have varying agonist activity at kappa receptors. The mu-1 aspect of the receptor is responsible primarily for analgesia and the mu-2 for other, largely adverse, opioid effects. Numerous subtypes of the mu-1 receptors have been isolated and cloned, clearly indicating genetic polymorphism. Recent work on opioid agonist G protein coupled receptors, and specifically beta arrestin, has elucidated our understanding of biased ligands that helps explain the mechanisms by which opioids cause some adverse effects. This offers promise of new agents which offer full analgesia with fewer adverse effects.1, 2, 3, 4, and 5