1.13 Analgesia Flashcards
What are the NSAIDs we need to know?
ibuprofen, aspirin , paracetamol (starting page 6)
How is aspiring taken?
oral
What occurs to aspirin after ingestion?
rapidly hydrolyzed to esterases salicylate
What is the half life of aspirin?
4-15hrs (Dose dependent)
What are the unwanted effects of aspirin
Low doses; GI irritation, hypersensitivity
Salicylism (high doses); tinnitus, vertigo, decreased
hearing
Reye’s syndrome; rare childhood disorder
Interactions; warfarin
How does aspirin have analgesic effect?
decreased prostanoid synthesis
leads to less sensitisation of
nociceptors to effects of mediators
e.g. 5-HT, kinins etc
How does aspirin have antipyretic effect?
centre in hypothalamus regulates body temperature • in fever temp raised due to synthesis of PGE2 due to pyrogens • aspirin decreases PGE2 synthesis
How does ibuprofen have analgesic effect?
• decreased prostanoid synthesis
leads to less sensitisation of
nociceptors to effects of mediators
e.g. 5-HT, kinins etc
WHat are the routes of administraiton of paracetamol?
oral, rectal and IV
How does aspirin have antipyretic effect?
• centre in hypothalamus regulates body temperature • in fever temp raised due to synthesis of PGE2 due to pyrogens • aspirin decreases PGE2 synthesis
What are the unwanted effects of paracetamol?
how common
uncommon, allergic skin reactions, hepatotoxicity with chronic use or overdose
What are the 3 types of opoid receptor?
2) where are they found?
3) which is responsible for most the therapuetic effects of opoid analgesics? (agonist or antagoinst)
4) What type of receptor are they? What enzyme they effect (activate or inhibit)?
1) 2) u, delta (peripheral pain) and k (spinal pain)
3) u (agonist)
4) G-protein linked, inhibit adenylate cyclase
What are the 3 types of opoid receptor?
2) where are they found?
3) which is responsible for most the therapuetic effects of opoid analgesics? (agonist or antagoinst)
4) What type of receptor are they? What enzyme they effect (activate or inhibit)?
1) 2) u, delta (peripheral pain) and k (spinal pain)
3) u (agonist)
4) G-protein linked, inhibit adenylate cyclase
Name 3 opoid neurotransmitters
enkephalins
endorphins
dynorphins
Name 2 morphine anatlogues that are opoids:
2) Name 2 synthetic derivatives that are opoids:
Morphine analogues diamorphine (heroin) codeine Synthetic derivatives pethidine Dextropropoxyphene
What are the 2 therapeutic effects of opioid analgesics?
analgesia and euphoria sedation
Opioid Analgesics
1) route of administraiton
2) describe absorbtion from __a___
3) does it undergoe 1st pass metabolism?
ADME
oral, rectal, i.v., i.m.
erratic absorption from gut
extensive first pass metabolism
What type of opioid is given for severe pain?
2) given for mile pain?
3) 2 can also be given for…
1) mophine and pethidine
2) codeine, dextropropxyphene and dihydrocodeine
3) cough suppresive and antidiarrhoeal