NSAIDs Flashcards
What is the mechanism of action of NSAIDs?
Inhibition of COX –> reduce production of prostaglandin mediators
COX1 – maintains gastric mucosa integrity, renal parenchyma, platelet aggregation
COX2 – mediates pain and inflammation at sites of injury
What are the non-specific COX inhibitors?
Salicylates Ibuprofen Naproxen Acetaminophen Ketorolac
What are the specific COX2 inhibitors?
Celecoxib
Describe metabolism of salicylates
Rapidly absorbed from small intestine
Metabolized in liver to salicylic acid
What are side effects of salicylates?
GI upset Dyspepsia Bleeding Tinnitus Allergic reaction
How does the side effect profile of ibuprofen and naproxen differ from that of salicylates?
Less GI irritation and dyspepsia
Renal toxicity in patients with pre-existing renal disease
Describe metabolism of acetaminophen
Converted by conjugation and hydroxylation in liver to inactive metabolites (and NAPQI [hepatotoxic] at high doses)
How does the side effect profile of acetaminophen compare to salicylates?
No interaction with platelets - no increased risk of bleeding
No GI irritation
Potential hepatotoxicity with high doses due to NAPQI
What is unique about Ketorolac?
It is a non-selective COX inhibitor and also potentiates actions of opioids (almost as effective as morphine but without the ventilatory and cardiac depression)
Describe metabolism of Ketorolac
Glucuronic acid conjugation in liver
What are side effects of Ketorolac?
Bleeding risk Bronchospasm in ASA sensitive patients GI irritation Renal toxicity Hepatic toxicity
How do selective COX2 inhibitor differ from non-selective?
Lacks inhibition of platelet aggregation and decreased GI side effects
