Neuropathic Pain / Other Treatments Lecture

Question 1

What are the classifications of low back pain in the 2017 guidelines?

Answer 1

Acute: <4 weeks.
Subacute: 4–12 weeks.
Chronic: >12 weeks.

Question 2

Recommendations for acute/subacute LBP?

Answer 2

non-pharm preferred : Heat/massage/acupuncture/spinal manipulation
If medications are required – NSAIDs and/or skeletal muscle relaxants

Question 3

Treatment recommendations for chronic LBP?

Answer 3

1st line: non-pharm options: exercise/mindfulness practices/yoga/tai chi/biofeedback/ cognitive behavioral treatment/spinal manipulation
If there is a poor response consider pharmacotherapy in this order:
1) NSAIDs
2) tramadol or duloxetine
3) opioids (only after risks/benefits are weighed)

Question 4

negative aspects of muscle relaxants?

Answer 4

CNS depression (dizziness, confusion, coordination)

Dependence (avoid combo w/ alcohol, benzos, opioids)

Withdrawal (potentially life-threatening in severe cases)

Question 5

what are first line agents for neuropathic pain?

Answer 5

Gabapentin - affects descending noradrenergic and sertonergic pain transmission pathways
Amitriptyline - inhibition of serotonin and/or norepinephrine in CNS
SNRIs - (Duloxetine & Venlafaxine) - ^^

Question 6

What are common side effects of neuropathic pain medications?

Answer 6

Gabapentin/Pregabalin: Sedation, GI upset.
TCAs: potentially fatal arrhythmias, sedation
SNRIs: Suicidal ideation (1st 2–4 weeks), headache, sedation

Question 7

what are third/fourth line agents for neuropathic pain?

Answer 7

cannabis
botox
opioids
SSRIs

Question 8

in the endocannabinoid system - what’s the difference between CB1 and CB2 receptors?

Answer 8

CB1 = CNS. Mood, motor tone, cognition, peripheral nervous system (visceral sensation)

CB2 = periphery. cellular & humoral response to neuroinflammation and pain

Question 9

What are the key components of medical cannabis?

Answer 9

THC: Partial CB1/CB2 agonist → muscle relaxation, sedation, analgesia.
CBD: CB1/CB2 antagonist → fewer analgesic effects, modulates other systems (5HT, TRPV)

Question 10

What are the pros and cons of smoked cannabis for pain?

Answer 10

Pros: May improve subjective symptoms (pain, stiffness, relaxation).
Cons: Insufficient evidence for safety/effectiveness in MS-related spasticity or fibromyalgia