COX inhibitors Flashcards
What are the 3 main therapeutic actions of Cylooxygenase inhibitors?
Anti-inflammatory
Analgesic (Pain relief)
Antipyretic (Fever relief)
What are NSAIDs?
Group of drugs that inhibit cyclooxygenase enzymes.
What step[s] does NSAIDs inhibit?
Inhibits cyclic endoperoxides.
What are the differences between COX-1 and COX-2 enzymes?
COX-1 = Constituive in most tissues
COX-2 = Inducible under certain conditions such as; inflammatory response (In times of need)
Where are COX-1 and COX-2 found respectively?
COX-1 = Kidney, Stomach, Platelets
COX-2 = Macrophages, Leukocytes, Fibroblasts
What mechanism does paracetamol work on?
COX-3 Inhibitor, localised effect in the CNS
What is Etoricoxib?
Selective COX-2 Inhibitor
Given orally for pain, inflammation in osteoarthritis.
RA and acute gout.
What is Celecoxib?
Selective COX-2 Inhibitor.
For pain, inflammation in RA and osteoarthritis
What are prostanoids?
Lipid mediators generated by the action of COX.
Controls contraction/relaxation of smooth muscle and constriction and dilation of blood vessels.
What are COX-inhibitors derived from?
Membrane phospholipids
What is the mechanism of action for NSAID anti-inflammatory effect?
Decrease in PGE2, PGI2 reduces vasodilation and oedema
What is the mechanism of action for NSAID analgesic effect?
Decrease in PGI2, reduces sensitisation of nociceptive nerve endings to bradykinin.
What is the mechanism of action for NSAID antipyretic effect?
Decrease in PGE2, reduces the temperature ‘set point’ in the hypothalamus.
What is the difference in binding sites of COX-1 and COX-2 inhibitors?
COX-2 has a side pocket attached to the Hydrophobic ‘tunnel’. Selective COX-2 inhibitors bind to this.
What are some of the therapeutic benefits of COX-2 selective drugs?
GI
Kidneys
Cardiovascular System
GI = reduced musus and bicarbonate secretions
Reduced mucosal blood flow
Kidneys = Decreased GFR due to reduced bloof flow
Cardiovascular system = Increases blood pressure
