Back to the Basics
Unique Features
Special Populations
Side Effects
The Non-Agonists
100

These two opioids inhibit the NMDA receptors 

Tramadol, Methadone

100

This opioid has the longest half-life

Methadone
100

Dosing a remifentanil infusion by this method will lead to dramatically higher concentration in obese patients

Total Body Weight

100

Reduction of this lead to constipation from opioids

peristalsis 

100

The partial agonists will exert this mechanism when administered with a full agonist such as morphine or fentanyl

competitive antagonism 

200

Originating from injured nerve terminals, this pain mediator activates nociceptors

Glutamate
200

The ester structure of this opioid allows it to be metabolized by hydrolysis from nonspecific esterases

Remifentanil 

200

In kidney failure, this metabolic byproduct can accumulate and lead to life-threatening respiratory depression due to its analgesic potency rivaling its parent compound

Morphine 6-Glucuronide

200
Non-histamine releasing opioids generally reduce MAP by decreasing this

Heart Rate

200

Better not give this opioid to your depressed patient with a vancomycin-resistant staph aureus infection

Tramadol

300

neuraxial opioids relieve pain by activating mu receptors in this area of the spinal cord 

Substantia gelatinosa

300

This synthetic is a great choice for infusion when significant intraoperative stimulation and post-operative pain are expected

sufentanil

300

Giving this opioid to your ESRD patients can lead to excitatory CNS effects including anxiety, tremulousness, myoclonus, and frank seizures

Meperidine

300

Opioids reduce minute ventilation by reducing this

Respiratory Rate
300

Least likely to increase biliary sphincter tone, this agonist-antagonist is great for biliary colic and labor analgesia

Butorphanol

400

Mu agonists are best at treating "second pain" sensations that are carried by this slow conducting, unmyelinated fiber

C-fibers

400

Along with the liver, this organ helps with biotransformation of fentanyl through carboxylesterases

Lung

400

This metabolite of hydromorphone has no analgesic properties, and can accumulate in ESRD leading to potential neurotoxicity, myoclonus, and restlessness  

Hydromorphone-3-glucoronide

400

High dose opioid anesthesia was traditionally used for cardiac surgery but abandoned due to this major complication

intraoperative awareness

400

Unlike naloxone, this agonist-antagonist can reverse opioid-induced ventilatory depression while maintaining some analgesia

nalbuphine 

500

Miosis from opioids is produced by activation of this nucleus in this cranial nerve

Edinger-Westphal nucleus in CNIII

500

Bolusing these three opioids will lead to decreased SVR via release of this compound

morphine, meperidine, hydromorphone

histamine

500

liver failure usually does not have a major impact on opioid pharmacokinetics with the exception of this phase during liver transplantation 

Anhepatic phase

500

nausea and vomiting from opioids are triggered by activation of this brain region near this ventricle 

chemoreceptor trigger zone in the 4th ventricle

500

Naltrexone utilizes this mechanism to treat OUD and this substance use disorder

competitive antagonist and AUD