Unit 9: Analgesia Flashcards
Name some of the body’s responses to pain
bradykinin serotonin histamine K+ ions acids prostaglandins substance P
Arachadonic Acid is a precursor to what? (Think: pain modulation)
prostaglandins
leukotrienes
Name the cyclooxygenase enzymes
COX-1
COX-2
Where are COX-1 receptors typically found?
CNS mucosa kidney endothelium bronchi GI Tract PLT
Where are COX-2 receptors typically found?
bone brain kidneys GI tract female reproductive system
What is the main function of COX-1?
housekeeping
protective effects
Name some effects of COX-1
decrease in gastric acid secretion
increase in mucous secretion
regulate blood circulation
regulate vascular tone and PLT function
What typically induces COX-2?
trauma
inflammatory chemical mediators causing pain
What 2 prostanoids work together to regulate BP?
thromboxane
prostaciclin
What do prostaglandins do?
regulate inflammatory mediation
construct vascular smooth muscle
regulate PLTs
induce labor
Name 3 prostanoids
prostaglandins
thromboxane
prostacyclin
What does prostacyclin do?
stop continual bleeding
What does thromboxane do?
brings PLTs to the site of injury (PLT aggregation) to prevent bleeding
What causes pain/edema in the body?
bradykinin/histamines in the inflammatory process
How do the NSAIDs work?
inhibit prostaglandin synthesis by inhibiting COX-1 and COX-2
Why are the NSAIDs good for joint pain?
all can be found in the synovial fluid after repeated dosings
Benefit of newer NSAIDs
more selective for COX-2 –> do not inhibit PLT function
Risk of children taking ASA
Reye’s Syndrome
Symptoms of ASA Toxicity
increased heart rate tinnitus hearing loss dimness of vision headache N/V/D dizziness confusion
How is ASA toxicity treated?
charcoal + dialysis
Only 2 COX-2 selective inhibitors on the US market
celecoxib (Celebrex)
meloxicam (Mobic)
major risks of COX-2 selective inhibitors
increased risk of:
MI
stroke
What is diclofenac?
non-selective COX inhibitor
Advantages of diclofenac
older
cheaper
GI ulceration less frequent
