eicosanoids & NSAIDs Flashcards
5 cardinal signs of inflammation
Calor (heat), Rubor (redness), Tumor (swelling), Dolor (pain), Loss of function
What induces COX-2 expression?
Inflammatory cytokines like IL-1β and TNF-α
Which prostanoid promotes platelet aggregation
TXA₂
Which prostanoid inhibits platelet aggregation
PGI₂
Which prostanoid is most associated with pain sensitization?
PGE₂
How does aspirin inhibit COX enzymes
Irreversibly acetylates COX-1 and COX-2
What is unique about aspirin’s action on platelets
Irreversibly blocks platelet COX-1 → ↓ TXA₂ → anti-platelet effect
What enzyme does paracetamol inhibit and where?
Possibly COX-3, selectively in the CNS
celecoxib
Selectively inhibits COX-2
how do nsaids causeGI side effects?
Inhibits COX-1 → ↓ PGE₂ → loss of gastric protection
What causes aspirin-induced asthma
Shunting of arachidonic acid to leukotriene pathway (↑ leukotrienes)
Why is celecoxib associated with cardiovascular risk
COX-2 inhibition → ↓ PGI₂ but not TXA₂ , rel increase in TXA2 →platelet aggregation, pro-thrombotic state
advantages of paracetamol
spares GI tract, gd analgesic & antipyretic, few side effects & DDIs, rel safe for paediatric use
NSAIDs AEs
GI upset, N&V, ulceration, pseudoallergic rxn, renal failure, lower GFR, pregnancy toxicity, high dose: dizziness, deafness, tinnitus, (non-aspirin) risk of heart attack.stroke
aspirin AEs
bleeding due to blood thinning effect, aspirin-linnked Reye’s syndrome in children w viral infection, aspirin-induced asthma
what causes GI side effects of NSAIDs
Inhibits COX-1 → ↓ PGE₂ → loss of gastric protection
