Pain Flashcards
Morphine
Opiate agonist
Indicated for acute/chronic severe pain
Observe for tolerance (dif than addiction)
ADRs:
- resp. depression most serious ADR»_space;> monitor RR; HOLD if RR <12
- orthostatic hypotension»_space;> monitor BP; HOLD if SBP <90
- Constipation, urinart retention, N/V, sedation
- INTERACTS with any CNS/resp. depressant
- can build tolerance, no dose limit
- habit forming
Inflammatory neurotransmitters
Histamine Prostaglandins Bradykinins Nitric oxide NE
Excitatory/fast neurotransmitters
Glutamate
Aspartate
Inflammatory neuro-Ts
Inhibitory/slow neuro-Ts
GABA Glycine DA Serotonin Endorphins
A-delta fibers
Quick, myelinated
Well localized pain
Transmits somatic pain signals
C-fibers
Unmyelinated, slow
Poorly localized
Transmits visceral pain signals
Hyperalgesia
excessive pain sensitivity
Allodynia
pain perception cause by non-painful stimuli
Ectopic discharge
pain signaling in absence of stimuli
Non-opioid analgesics
Acetaminophen
NSAIDS
Salicylates
COX-2 inhibitors (used for acute pain)
Opioids in elderly
Common SE: confusion, renal impairment - cumulative effect if pt on antibx
Risk factors: resp. dx, sleep apnea
Naloxone (Narcan)
- Opioid antagonist/antidote to opioid OD
- Blocks mu and kappa receptors
- Reverses CNS and resp. depression - puts pt into immediate withdrawal (tremor, hypervent.)
- Only effective for 20 mins, may have relapse of resp. depression
Tramadol (Ultram)
Partial opioid agonists-antagonists (stim some receptors, antagonize others)
For moderate-severe pain
ADRs: sedation, constipation, tolerance/dependence, worse w/ etoh & benzos
Opiate ADRs
Sedation, drowsiness, mental clouding
Constipation, N/V
Tolerance/dependence
ADRs worse w/ etoh or benzos
COX inhibitors
Non-selective:
NSAIDS
Salicylates/aspirin
Selective:
Celexocib (Celebrex)
MOA: Inhibits PG formation relieve mild-mod pain antipyretic effects (tx fever) anti-inflammatory effects (tx arthritis) antiplatelet (tx MI, CVA)
Celexocib (Celebrex)
Selective COX-2 inhibitor
Indications: pain, inflammation
Better than NSAIDs w/ GI irritation b/c doesn’t block all COX, only COX-2 (remember PGs needed for mucus lining in stomach)
Black box: incr risk MI, CVA, death
ADRs: GI bleeding, HTN, edema, renal insufficiency
Avoid use in pts with coronary artery bypass d/t black box (incr risk for MI)
Ibuprofen
NSAID
Inhibits PG syn in CSN
ADRs: GI ulcers, renal failure
Acetaminophen
Inhibits PG synthesis in CSN
Indicated for pain, fever
NOT anti-inflammatory, antiplatelet
Drugs for neuropathic pain
Act on same neuro-Ts involved in pain signaling in CNS - can turn don volume of pain
Anti-epileptics: gabapentin (Neurontin)
- modulates pain perception
Antidepressants: TCA amitriptyline (Elavil) SNRI duloxetine (Cymbalta)
Lidocaine
Why use opioid/NSAID combo?
(2) different MOA targets pain
Have a synergistic effect: can give less of each drug and have fewer SE
NSAID acts on pain & inflammation and opioid works on pain
Lidocaine
Topical analgesic
ADRs: CNS excitement, convulsions, resp. depression, cardiac arrest
Analgesics for sever pain
morphine
Analgesics for moderate pain
oxycodone (Oxycontin)
oxy w/ acetaminophen (Percocet)
Tramodol
Opiate agonist
Centrally acting opiate receptor agonists taht inhibits uptake of NE & serotonin - opioid & non-opioid mechanisms
Less resp depression than morphine
Indicated for mod - moderately severe pain
What drugs are used for cancer pain
Long-acting morphine
