Opioids MOA/PK
What type of G-protein-coupled receptor is involved with opioid activation?
Gi
this opioid is used an an antitussive (cough suppressant) in dogs. also used for mild pain.
hydrocodone
This NSAID has anti-endotoxic effects (septic shock).
flunixin meglumine (Banamine)
What type of channels do local anesthetics target?
transmembrane voltage-gated Na+ channel
What is the purpose of local anesthetic use as a constant rate infusion (CRI)?
1. analgesia for neuropathic pain
2. reduce the amount of inhalant anesthetic drug
3. prokinetic for treatment of ileus
Where are the presynaptic spinal receptors (mu, kappa, delta) located?
dorsal horn
this opioid is available in transdermal patches for long-term pain control.
fentanyl
This is a topical anti-inflammatory cream used in horses to control pain and inflammation associated with osteoarthritis.
Diclofenac (Surpass)
What additives enhance the effect and extend the duration of the block?
alpha-2 agonists, opioids, ketamine
This binds to voltage-dependent Ca2+ channels on neurons, inhibiting exocytosis of excitatory neurotransmitters. It is used for neuropathic pain and MSK inflammatory conditions (including laminits in equine).
Gabapentin
This opioid receptor mediates most of the analgesic effects.
Mu receptor
these opioids are used for sedation and immobilization of large wild animals; extremely potent
carfentanil & etorphine
Grapiprant functions as an antagonist on what receptor?
prostaglandin EP4 receptor
Which systems show toxicity to local anesthetics?
CNS & cardiovascular system
(CNS toxicity seen at lower plasma concentrations than CVS toxicity)
This a2-agonist is used in pre-anesthetic sedation. It also is involved in post-op pain management, especially when combined with opioids.
dexmedetomidine
Opioids are ____-soluble and ____ bases. Favors _____ absorption.
lipid-soluble, weak bases, favors intracellular absorption
this opioid is not preferred in horses due to causing excitement and increased locomotor activity.
morphine
This oral paste/tablet or injectable medication is used in horses, and recommended only for 14 days.
Firocoxib (Equioxx)
What specific local anesthetic is associated with dysrhythmia (CVS toxicity)?
bupivacaine
This drug is an NMDA antagonist, opioid agonist, and is used for acute/chronic pain and neuropathic pain. Maintains airway/CV reflexes. can lead to dissociative effects
ketamine
Name a contra-indication for opioid use.
head trauma, hyperthermia in cats/horses/cattle/swine/goats, dogs panting
this opioid is more effective for uncontrollable pain, due to having a multimodal MOA. full mu agonist and NMDA antagonist
methadone
A 4 yo DSH FS cat presents with dyspnea, cyanosis, and tachycardia. The doctor decides to do bloodwork and finds the blood is discolored and resembles chocolate. The doctor decides to test the level of methemoglobin in the blood and discovers methemoglobinemia. What NSAID may this cat have ingested?
Acetaminophen
This local anesthetic is used to stabilize ventricular dysrhythmia.
lidocaine
Local anesthetics are ___ bases, ____ soluble, and bind to alpha-1 acid _____.
weak bases, lipid-soluble, alpha-1 acid glycoprotein