Cyclooxygenase inhibitors Flashcards
What enzyme breaks down arachidonic acid into prostaglandins?
cyclooxygenase
What are the effects of COX-1 activation?
GI PROTECTION: ↓gastric acid secretion, ↑ mucous production, maintenance of GI mucosal perfusion.
RENAL PROTECTION: maintenance of renal perfusion and renal function.
SMOOTH MSL: Vasodilation and bronchodilation
Regulates platelet aggregation
How does blocking COX-1 prevent against strokes?
Disrupts platelet aggregation
What happens when COX-2 is activated?
The inflammatory response sx (vasodilation, edema, pain, ↑ capillary permeability)
What are the possible risks of COX-2 inhibitors?
vasodilation is blocked but platelet aggregation still continues
T/F. ASA affects platelets irreversibly?
True
How do NSAIDs work?
They reduce the production of prostaglandins by blocking COX-1 and COX-2
Why should children who have chicken pox or flu sx not be treated with ASA?
d/t association with Reye’s syndrome
T/F Celecoxib (Celebrex) is a 2nd generation NSAID
True
Why is Celecoxib (Celebrex) a last choice NSAID drug?
It is a selective cox-2 inhibitor so it will have serious cardiovascular risks like MI and stroke b/c it does not have an antiplatelet effect
Why should NSAIDs be given with milk or food?
To prevent GI upset
What do you do if a pt with a feeding tube needs an NSAID?
Don’t crush enteric coated drugs instead call the pharmacy to send non enteric coated
Why does Acetaminophen not have anti-inflammatory characteristics?
it only blocks prostaglandins in the CNS not the periphery
What organ function are we concerned about when giving NSAIDs or Tylenol?
Tylenol- mainly liver
NSAIDs-kidney
What are the side effects of ASA and nonselective cox inhibitors?
they block COX1(and 2) so reduce protective prostaglandins which can lead to gastritis, gastric ulcers, or bleeding
Indications, MOA, and adverse effects of ACETAMINOPHEN?
Indication: Antipyretic and analgesic
MOA: inhibits prostaglandins in the CNS
Adverse effects: Steven Johnson syndrome, acute generalized exanthematous pustulosis, toxic epidermal necrolysis, hepatotoxicity, and hepatic necrosis
What is the dosage recommendation of acetaminophen for alcohol abuse pts?
no more than 2g
What labs should be considered before cyclooxygenase inhibitors administration?
Liver and kidney function
What is the antidote for acetaminophen poisoning?
Acetylcysteine
What can be given to balance out too much ASA?
Sodium bicarbonate
What are the s/sx of Reye’s syndrome?
irritability, confusion, vomiting, seizures, LOC
What is Reye’s syndrome?
Causes encephalopathy and fatty changes in the liver
