Flashcards in Neuro - Pharmacology (Opiod analgesics) Deck (19):
Name 8 opioid analgesics.
(1) Morphine (2) Fentanyl (3) Codeine (4) Loperamide (5) Methadone (6) Meperidine (7) Dextromethorphan (8) Diphenoxylate
Detail the mechanism of opioid analgesics.
Act as agonists at opioid receptors (mu = morphine, delta = enkephalin, kappa = dynorphin) to modulate synaptic transmission - open K+ channels, close Ca2+ channels --> decrease synaptic transmission. Inhibit release of ACh, norepinephrine, 5-HT, glutamate, substance P
How do opioid analgesics act? Where exactly do they act (give specific receptors)?
Act as agonists at opioid receptors (mu = morphine, delta = enkephalin, kappa = dynorphin)
What are 5 substances of which opioid analgesics inhibit the release?
Inhibit release of ACh, norepinephrine, 5-HT, glutamate, substance P.
What are 2 clinical uses applicable to all opioid analgesics?
(1) Pain (2) Acute pulmonary edema
What is a clinical use for dextromethorphan?
What are 2 opioid analgesics used clinically for diarrhea?
Loperamide and diphenoxylate
What is a clinical use for methadone?
Maintenance program for heroin addicts
What are 5 toxicities to be associated with opioid analgesics and/or their use with other drugs?
(1) Addiction (2) Respiratory depression (3) Constipation (4) Miosis (pinpoint pupils) (5) Additive CNS depression with other drugs
To which 2 toxicities of opioid analgesics does tolerance not develop?
Tolerance does not develop to miosis and constipation
How is opioid analgesic toxicity treated?
Toxicity treated with naloxone or naltrexone (opioid receptor antagonist)
What kind of drug is butorphanol? Exactly what kind of receptor does it act upon, and how? What effect does this have?
Mu-opioid receptor partial agonist and kappa-opioid receptor agonist; Produces analgesia
What is a clinical use for Butorphanol?
Severe pain (migraine, labor, etc.)
What is the advantage of Butorphanol over some other opioid analgesics?
Causes less respiratory depression that full opioid agonists
What toxicity is associated with Butorphanol, and in what context?
Can cause opioid withdrawal symptoms if patient is also taking full opioid agonist (competition for opioid receptors)
What is significant to know about the treatment of Butorphanol toxicity?
Overdose not easily reversed with naloxone
What kind of drug is Tramadol? What effects does it have?
Very weak opioid agonist; Also inhibits secretion and norepinephrine reuptake (works on multiple neurotransmitters - "tram it all" in with TRAMADOL)
What the clinical use for Tramadol?