Pharm 10 Opioids

Question 1

Main analgesic receptor

Answer 1

Mu Opioid Receptor (G-protein)

Question 2

Opioid Receptor MOA

Answer 2

1. Decrease Ca current (decrease NT release)

2. Increase K current (Hyperpolarize)

Question 3

Nociceptive afferent synapse

Answer 3

Dorsal Horn

Question 4

Descending pathway synapse

Answer 4

Modulate dorsal horn via interneuron

Question 5

Main Opioid effect

Answer 5

Block Glutamate and Substance P release at Dorsal Horn synapse

Question 6

Opioid effect on Rostral Ventral Medulla

Answer 6

Block inhibition, let RVM inhibit Dorsal Horn

Question 7

Opioid effect on interneuron

Answer 7

Hyperpolarize, block excitatory drive to Dorsal Horn

Question 8

Only Opioid effect not mediated by Mu receptor

Answer 8

Psychotomimesis

Question 9

Morphine problem

Answer 9

Poor lipid solubility

Question 10

-Morphine-

MOA

Answer 10

MOR

Question 11

-Morphine-
Metabolism
Major SE

Answer 11

CYP450

Respiratory depression

Question 12

-Morphine-

CI

Answer 12

MAOI

Alcohol

Question 13

-Fentanyl-
Indication
MOA

Answer 13

Severe pain

Very potent MOR (100x morphine)
Very lipophilic

Question 14

-Fentanyl-

Useful application

Answer 14

Transdermal patches

Question 15

-Fentanyl-

SE

Answer 15

Less nausea

More muscle rigidity

Question 16

-Methadone-
Indication
MOA

Answer 16

Analgesia and Heroin withdrawal

Potent MOR agonist

Question 17

-Meperidine-

Answer 17

MOR agonist

Less potent and quicker than morphine

Question 18

-Meperidine-

Unusual effects

Answer 18

Doesn’t prolong labor
Not antitussive
Less constipation

Question 19

-Meperidine-

SE

Answer 19

Toxic metabolites
Tachycardia
Dysphoria

Question 20

-Codeine-
Indication
MOA

Answer 20

Moderate pain
Cough suppressant

MOR, unless you have CYP2D6 mutation (10%)

Question 21

-Codeine-

Metabolism

Answer 21

CYP450

Need to metabolize to morphine with CYP2D6

Question 22

-Propoxyphene-

Answer 22

Toxic Psychosis

Heart Toxicity

Question 23

-Oxycodone-
Indication
MOA

Answer 23

Moderate pain
+acetaminophen = percocet

MOR

Question 24

-Hydrocodone-

Answer 24

Moderate pain

+acetaminophen = vicodin

Question 25

-Tramadol-
Indication
MOA

Answer 25

Use with Naloxone to get analgesic w/o respiratory depression

5HT & NE reuptake blocker
Very weak MOR until metabolized by CYP2D6

Question 26

-Tramadol-
SE
CI

Answer 26

Seizures

SSRIs, MAOIs

Question 27

-Pentazocine-
Indication
MOA

Answer 27

Moderate pain, but has ceiling effects
Formulated with naloxone to prevent euphoria (IV only)

KOR agonist
Partial MOR antagonist

Question 28

-Pentazocine-

SE

Answer 28

Increase HR/BP
Psychotomimesis
Anxiety

Question 29

-Buprenorphine-
Indication
MOA

Answer 29

Strong analgesic
Decrease addiction cravings

KOR antagonist
Partial MOR agonist

Question 30

-Buprenorphine-

SE

Answer 30

Less respiratory depression

More sedation

Question 31

Opioid antagonists:

Need higher doses for 2 drugs

Answer 31

Buprenorphine

Pentazocine

Question 32

-Naloxone-

Answer 32

Fast onset, fast offset (complete first-pass metabolism)

Need multiple injections

Question 33

-Naltrexone-

Answer 33

More potent, longer half life
Helpful for addiction
Don’t give for people with pain or dependence

Question 34

Tx strategy for moderate pain

Answer 34

Moderate opioid in combination with acetaminophen or aspirin

Question 35

Effect of giving a partial agonist to a patient already taking a full agonist

Answer 35

Precipitate withdrawal, pain

Question 36

Opioid interaction with MAOIs

Answer 36

HTN