Antipyretic Drugs Flashcards
Initial fever response is mediated by…
ceramide release in neurons in the anterior hypothalamus
The late response to fever is mediated by…
stimulation of COX2 which triggers the production of PGE2
PGE2 can cross the blood brain barrier and acts on …
EP3 and EP1 receptors on thermosensitive neurons
How do NSAIDs suppress fever?
They inhibit PGE2 synthesis
PGE2 production is catalyzed by PGE synthase in …
blood vessels (mostly in the brain)
3 major actions of NSAIDs
- Analgesic (reduce pain)
- Anti-pyretic (reduce fever)
- Anti-inflammatory (reduce inflammation)
Why is acetaminophen (tylenol) NOT an NSAID?
Acetaminophen is NOT anti-inflammatory (but it is analgesic and anti-pyretic
4 major actions of aspirin )an NSAID)
- Anti-inflammatory
- Anti-pyretic
- Analgesic
- Anti-platelet/anti-thrombotic
What is unique about the effect of aspirin on PGE2?
IRREVERSIBLE inhibition of PGE2 production
Aspirin decreases platelet production of … to limit platelet aggregation
TXA2 by COX-1
Adverse reactions of aspirin/NSAIDs
- GI bleeding
- Effects on pregnancy
- Renal effects (reduce GFR)
- Sensitivity
- Ulceration
- Obstruction
Aspirin use is avoided in children with viral illness because…
it can lead to Reye’s syndrome (brainstem dysfunction)
What risk factors increase the risk of having GI effects when using aspirin and NSAIDs?
- Age >65
- History of peptic ulcer or bleeding
- Multiple NSAID use
- High dose use
- Alcohol
- Anti-coagulant use
Why do NSAIDs have an effect on the GI?
Du to the loss of the cytoprotective actions of gastric prostaglandins
NSAID effects on gestation (3)
- May prolong gestation
- May require transfusion
- May cause premature closure of the ductus arterioles (which can cause fetal hypertension)
NSAIDs promote sodium…
retention
Aspirin salicylate (ASA) half-life
15 minutes
Aspirin overdose will cause … (2)
- metabolic acidosis
- respiratory alkalosis
Unlike with ASA, inhibition of COX2 by ibuprofen (advil) is…
reversible
