Pharmacology of pain Flashcards
How many pain be treated
NSAIDS
Opiods
Adjuvant therapy
What drugs target to site of trauma
Local anaesthetics
Anti-inflammatory drugs
What drugs target first order neurones
Local anaethetics
What drugs target the dorsal horn
Local anaesthetics
Opiods
Alpha 2 agonist
What drugs target the brain
Opiods
Alpha 2 agonists
What pathway do opiods use
Supraspinal analgesia pathway
Name 2 endogenous opiods
Enkephalin and dynorphin
What 3 main receptors do opiods target
Mu receptors
Delta receptors
Kappa receptors
Describe the mechanism of action that opiods use
Reduced calcium influx
Reduced neuronal excitability
What is meant by peripheral sensitisation in terms of sensitisation
Decreased pain threshold at the site of injury
Define hyperalgesia
Increased response to harmful stimulus
What is seen in peripheral sensitisation
Primary thermal hyperalgesia
Primary mechanism hyperalgesia
What is central sensitisation in terms of pharmacology
Increased excitability at CNS neurones from prolonged activity
What is seen in central sensitisation
Secondary hyperalgesia
Mechanism allodynia
Define allodynia
Increased response to a non harmful event
What is the mechanism behind peripheral sensitisation
Ectopic impulse generation at injury site
Ephatic connections between injured and uninjured
What do NSAIDs target
COX-1 and COX-2
How do nociceptors stimulate second order neurones at dorsal horn
Release of glutamate and peptides
Where does glutamate act upon
AMPA and NMDA receptors in spinal cord
What is the result of persistent activation of AMPA and NMDA receptors
Altered gene expression
Increased intracellular calcium levels
Upregulation of prostaglandins and cox enzymes
What is adjuvant therapy
Anti-depressant
Anti-epileptics
Used for neuropathic pain
Name 3 useful drugs used in adjuvant therapy
Pregabalin
Gabapentin
Tricyclic antidepressants
What receptors do drugs acts on
GABAb and alpha 2 delta calcium channels
Give 3 examples of local anaesthetics
Lignocaine
Bupivacaine
Prilocaine
What is the most common facial pain syndrome
Trigeminal neuralgia
What is trigeminal neuralgia
Sudden, paroxysmal attacks of pain Electric shock like Stabbing Sharp Unilateral
Most common cause of trigeminal neuralgia
Compression, distortion stretching on nerve V root fibres by branch of anterior or posterior inferior cerebellar artery
