Pain Medications Flashcards
Morphine MOA
mu receptor agonist
Morphine Duration of Action
1-4 hours
Morphine Therapeutic Use
perferred for epidural administration
severe acute pain in dogs, cats and horses
Morphine Adverse Effects
dogs: panting, high doses can cause convulsions/excitement
cats: excitation at high doses
horses: safe, excitement, increased locomotor activity DO NOT use 7 days prior to race
pigs: excitement
NOTE wide margin of safety
Hydromorphone MOA
mu receptor agonist
Hydromorphone Duration of Action
2-4 hours
Hydromorphone Adverse Effects
dogs: emesis, panting, dysphoria
cats: hyperthermia
Hydromorphone potency compared to morphine
7x more potent than morphine
Hydrocodone MOA
mu agonist
Hydrocodone Therapeutic Use
mild - mod pain
antitussive (good oral bioavailability)
Common combination of hydrocodone
hydrocodone + acetaminophen
Hydrocodone potency compared to morphine
6x more potent
Codeine MOA
mu agonist
Codeine Therapeutic Use
mild - mod pain
antitussive
Codeine potency compared to morphine
similar to morphine
Methadone MOA
NMDA antagonist
inhibits reuptake of neurotransmitters
Methadone Therapeutic Use
uncontrollable pain in horses
minor procedures in horses
anesthetic premed in small animals
Benefits of using Methadone in horses
sedation but animal does not become recumbent
Fentanyl MOA
mu agonist
Fentanyl Onset of Action
rapid
Fentanyl potency compared to morphine
100x more potent than morphine
Fentanyl Therapeutic Use
transdermal solution for dogs: analgesia for 96 hours
chronic pain after sx
Fentanyl Adverse Effects
respiratory despression
Remifentanil MOA
mu agonist
Reminfentanil Therapeutic Use
indution of anesthesia
Remifentanil Metabolism
metabolized tissue and plasma esterase - rapid clearance (half-life 3-6 min)
safe for heaptic or kidney disease patients
Carfentail and Etorphine MOA
mu agonists
Carfentanil and Etrophine Therapeutic Use
used for zoo and wildlife animals
Burprenorphine MOA
partial mu agonist
kappa antagonist
Buprenorphine Duration of Action
6-12 hours
slow onset
Buprenorphine Therapeutic Use
analgesia
Buprenorphine Adverse Effects
respiratory depression
requires a high dose of naloxone to reverse these effects
Buprenorphine potency compared to morphine
25x more potent than morphine
Simbadol (buprenorphine) MOA
mu agonist
Simbadol Therapeutic Use
approved for use in cats
24 hour analgesia
Butorphanol MOA
kappa agonist
mu antagonist
Butorphanol Duration of Action
30-90 min
Butorphanol Therapeutic Use
short acting analgesia in horses
maintain analgesia CRI
Butorphanol Adverse Effects
mild sedation
Nalbuphine MOA
kappa agonist
mu anatgonist
Nalbuphine Therapeutic Use
mild - mod pain
reverse respiratory depression caused by mu agonists
Pentazocine MOA
kappa agonist
mu partial agonist
Pentazocine Therapeutic Use
less sedation
horses: colic pain
dogs: post-op pain
Naloxone MOA
GABA antagonist
mu antagonist
Naloxone Therapeutic Use
administered every 2-3 min to reverse respiratory depression in emergency conditions caused by opioids
Naltrexone MOA
competitve antagonist for all opoid receptors
Naltrexone Therapeutic Use
reversal agent for carfentanil overdose - long acting
Nalmefene MOA
mu antagonist
Nalmefene Therapeutic Use
reversal of fentanyl induced respiratory depression
Tramadol MOA
complex muscarinic antagonist
Tramadol Therapeutic Use
pain reflief
Acetaminophen MOA
COX inhibitor
Acetaminophen Duration of Action
dogs: 8-12 hours
horses: 12 hours
Acetaminophen Therapeutic Use
central analgesic drug
Acetaminophen Adverse Effects
hepatic damage
methemoglobinemia in cats
How to treat acetaminophen induced methemoglobinemia in cats
treat with N-acetylcystine, blood transfusion and supportive care
Gabapentin MOA
a2-delta subunit of voltage gated Ca2+ channels on neurons
calcium channel blockers
Gabapentin Therapeutic Uses
controlling seizures
OA pain in cats
neuropathic pain
laminitis in horses
Gabapentin Adverse Effects
sedations
Amantadine MOA
NMDA aantagonist
Amatandine Duration of Action
12-24 hours
Amantadine Therapeutic Effects
analgesia in dogs
combined with NSAIDs
antiviral
Monoclonal Antibodies doe Anglesia =
anti-nerve growth factor
mAb for Analgesia used in dogs
Ranevetmab
mAb for analgesia used in cats
Frunevetmab
mAb for Analgesia Adverse Effects
degradation products can be immunogenic
Resiniferatoxin MOA
irreversible nueronal cell death
activate transient vanilloid receptor - Ca2+ influx after binding
Resiniferatoxin Therapeutic Use
bone cancer in dogs