Analgesia SEM2 Flashcards
What is an analgesic
A drug that specifically relives pain
What is the role of COX-1 enzyme
Expressed in tissue and protects the gastric mucosa, regulating blood flow and platelet function
What is the role of COX-2 enzyme
Induced in states of inflammation and pain to mediate them
What is the mechanism of action of non-steroidal anti-inflammatory drugs (NSAIDs)
Act by inhibiting the COX enzymes which reduces the production of prostaglandins
What do prostaglandins cause
Prostaglandins sensitise nociceptor nerve endings enhancing pain response
Act on capillaries to promote vasodilation - contributes to swelling and redness
How do local anaesthetics work
Block Na+ channels that conduct action potentials in sensory nerves e.g lidocaine
What are characteristics of local anaesthetist
Hydrophobic so can easily penetrate membranes
They are weak bases so readily protonated and resemble Na+ and block the channel
What are properties of endogenous opioids
Prominent gating role in the spinal cord to suppress input from nociceptors
Action in brainstem to activate descending inhibitory pathways
What type of receptors are opioid receptors
G protein-coupled receptors (GPCRs)
What are the 3 main types of opioid receptors
μ (mu), δ (delta), and κ (kappa) - all are inhibitory
What is medication commonly used for neuropathic pain
Gabapentin and pregabalin