12. Chronic Pain Flashcards
Difference between neuropathy, neuralgia, and neuritis
Neuropathy= Pain resulting from systemic disease
Neuralgia= Pain arising from Nervous system in response to non-painful stimuli
Neuritis= Pain from irritative non-neural disease
Examples of neuralgia, nueropathy and neuritis
Neuralgi= TN, MS, Vagoglossopharyngeal
Neuropathy= DM, Lupus, burning mouth (nutritional def.)
Neuritis=Odontogenic, post trauma, etc
What are the two types of Receptors responsible for activation of pain pathways
-EAA and tachykinin
EAA and Tachykinin neurotransmitters are
EAA= aspartate and glutamate Tachykinins= Substance P and neurokinin
What are the two different kinds of EAA receptors
AMPA and NMDA
Describe the difference between AMPA and NMDA
AMPA
- First pain
- Responds to low level release of glutamate
- Rapid and transient
NMA
- Second pain
- Response is delayed and prolonged due to aspartate release
- Delayed and prolonged
Antagonists of EAA receptors
Opioids
Antagonists of Tachykinin receptors
- Opioids
- Alpha 1 antagonists
- Alpha 2 agonist (cloniidine)
- TCA
- GABAB agonist (baclofen)
Side effects of long term NSAID use
- Gastric upset .
- Ulcers
- Blood dyscrasias (platelet inhibition)
- Potential teratogen
MOA of corticosteroids
Inhibition of Phopholipase A (decreases inflammation)
Uses for corticosteroids
- painful RA
- Nerve injury (adjuvant therapy)
Side effects of long term corticosteroid use
- Impaired wound healing and immunity
- Adrenal suppression
- Gastric irritation
- Hyperglycemia
MOA of Capsaicin
- Depletion of substance P
- Anti-inflammatory
Uses of capsaicin
- Poster herpetic neuralgia
- Osteoarthritis (painful)
Action of baclofen
GABAB agonist –> analgesia
Uses of baclofen
Neuropathic pain (TN, myofascial pain)
(more/less) abuse of baclofen compared to benzons
-less abuse than benzo
Uses of benzons
neuropathic pain (myofascial pain)
Side effects of benzons
- Dependence
- Withdrawl
- Teratogen
MOA of opioids (
Bind kapa receptors
Use of opiods
chronic pain
Side effects of opiods
- Abuse/dependence
- Sub-optimal pain control with recommended doses
MOS of TCA
inhibition of serotonin reuptake –> modulation of descending pain pathways
Uses of TCAs
Neuropathig pain (poster herpetic neuralgia, burning mouth, myofascial pain)
Side effects of TCA use
-Anti-cholinergic effects (i.e dry mouth)
Example of an alpha 1 antagonist is
guanethidine
Alpha 1 antagonist (increases/decreases) SNS activity Alpha 2 agonist
both decrease
Alpha 1 antagonist and Alpha 2 agonist used to treat
sympathetically mediated pain
Side effects of alpha 1 antagonists and alpha 2 agonists
-postural hypotension
Phenytoin is what class of drug
anticonvulsant
anticonvulsants are used to treat
neuralgias (conditions that result from damage to the nervous system)
Side effects of anti-convulsants used to treat neuralgias
Phenytoin= gingival hyperplasia
-Both result in ataxia, blood dyscrasia (i.e anemia and leukopenia)
Pregabalin is what drug classification
anti-convulsant
Pregabalin is similar to
gabapentin
Gabapentin is what class of drug
anti-convulsant
MOA of gabapentin
unknown- it is a gaba analog but doesn’t act on GABA receptor
Uses of gabapentin
TN
Side effects of gabapentin
ataxia, blood dyscrasia (leukopenia) , dizziness, same as other anti-convulsants
Uses of pregabalin
- Post herpetic neuralgia
- TN
Caution for pregabalin should be taken due to
life-threatening angioedema
Nerve blocks are used to treat
-myofascial pain, neurogenic pain
Sider effects with long term use of nerve block
- tissue trauma
- Scarring
- Infection
