NSAIDs Flashcards
Give 4 examples of NSAIDs
Aspirin, ibruprofen, diclofenac, indometacin
Name 3 actions of NSAIDs
Analgesia, anti-inflammatory, anti-pyuretic
How do they work?
By inhibiting prostaglandin synthesis by the cyclo-oxygenase pathway
Name 4 prostaglandins
PGD2, PGE2, PGF2a, PGI2
How are prostaglandins formed during inflammation?
Membrane phospholipids are converted to arachidonic acid via phospholipidase A2
COX-1 and COX-2 then convert it to PGG2->PGH2
-> prostaglandins via PG synthase
Apart from prostaglandins, what can arachidonic acid be converted into?
Leukotrienes and thromboxane (TXA2)
Aspirin is a -?
Salicylic acid
Ibruprofen and naproxen are -?
Propionic acids
An example of an acetic acid NSAID is-?
Indometacin
Name 2 selective COX-2 inhibitors
Celecoxib, etoricoxib
Roles of prostaglandins
Pain, inflammation (vasodilation), fever (PGE1 in hypothalamus), platelet aggregation inhibition, maintenance of renal blood flow, reduce gastric acid secretion, induces labour
How do prostaglandins have a role in pain
By sensitising nerves to bradykinin and histamine (produced from the tissue trauma)
What drug is given for MIs?
Low dose aspirin due to anti-platelet effect of TXA2 inhibition
(Thromboxane is also produced via COX)
Why is selective COX-2 inhibition beneficial?
Allows COX-1 to maintain physiological role of GI protection, renal blood flow maintenance and platelet aggregation
How do you reduce the side effect of gastric ulceration/bleeding?
Use COX-2 selective inhibitor
Enteric coated tablets
Combine with proton pump inhibitor
Combine with synthetic prostaglandin
