Pharmacology - Inflammation, pain and allergies Flashcards
Describe the mechanisms of action of local anaesthetics
Bind to intracellular voltage-dependent Na channels –> inactivate Na channels at specific sites with no loss of consciousness
What is the effect of lower pH (due to inflam and necrosis) on tissue penetration by amide-based local anaesthetics such as lignocaine?
Decreases tissue penetration –> require more drug
What is the mechanism of actions of NSAIDs?
Inhibit COX 1/2 and/or lipooxygenases to mitigate inflam, pain, pyrexia
Compare COX-1 vs COX-2 inhibitors
COX-1: production of PGs involved with mucus production, epithelial turnover, gastric acid secretion, renal perfusion and PLATELET aggregation
COX-2: mediates pain, gastric ulcer healing, renal perfusion, promotes angiogenesis and bone remodelling
Give and example of the follwing:
- Mixed COX1/2 inhibitor
- COX-2 preferential inhibitor
- COX-2 selective inhibitor
- Dual COX/LOX inhibitor
- PG2-EP4-Receptor antagonist
Mixed COX1/2 inhibitor: Aspirin, phenylbutazone, ketoprofen
COX-2 preferential inhibitor: Carprofen, meloxicam
COX-2 selective inhibitor: Deracoxib
Dual COX/LOX inhibitor: Ketoprofen
PG2-EP4-Receptor antagonist: Galliprant/grapiprant
Describe some of the potential adverse effects of using NSAIDs
- GIT toxicity: nausea, vomiting, ulcers
- Renal decompensation
- Hepatotoxicity
- Platelet dysfunction and bleeding
Describe the mechanism of action of opiods
Agonists, partial agonists or antagonists at Gi/Go-GPCRs (mu, kappa, delta)
Give 3 examples of very strong opiods (full agonists)
Morphine, methadone, fentanyl
Give 3 examples of partial opioid agonists
Buprenorphine, butorphanol, tramadol
Give 2 examples of opioid antagonists
Naloxone, Naltrexone
Describe some of the adverse effects of using opioids
- Hypotension
- Resp depression
- Histamine release
- Decreased peristalsis –> constipation
