Ch.19b: Opioids (Vickroy)

Question 1

4 opioids

Answer 1

butorphanol
morphine
fentanyl
naloxone

Question 2

Is naloxone CD?

Answer 2

NO. Nearly all other opioids are!!

Question 3

morphine class

Answer 3

opioid agonist

Question 4

butorphanol class

Answer 4

partial (mixed) opioid agonist. Stimulates some receptor subtypes, but antagonizes others of the same family

Question 5

fentanyl class

Answer 5

potent synthetic opioid agonist

Question 6

naloxone class

Answer 6

opioid antagonist

Question 7

main therapeutic uses of opioid drugs

Answer 7

• analgesic
• neuroleptanalgesic
• immobilization/restraint

Question 8

pain

Answer 8

unpleasant sensory and emotional experience assoc. with actual or potential tissue damage. Requires a functional CNS

Question 9

physio signs of pain

Answer 9

• CV activation
• inc. stress response
• hyperglycemia
• red. GI activity
• red. immune fx

Question 10

how is pain classified?

Answer 10

duration, anatomical location, site of origin

i.e. acute, chronic, cutaneous, somatic, visceral

Question 11

nociception**

Answer 11

ability to perceive and sense pain. Opiates produce “anti-nociception”

Question 12

analgesia

Answer 12

absence of pain in response to stimuli that are normally painful w/o loss of consciousness

Question 13

hyperalgesia

Answer 13

extreme responsiveness to stimuli that’s usually only mod. painful

Question 14

allodynia

Answer 14

pain caused by a stim. that woudn’t normally provoke pain

Question 15

analgesic

Answer 15

drug that block the formation, release or actions of substances that stimulate sensory n. endings (transuction) (i.e. NSAIDs, glucocorticoids)

Question 16

pain transmission pathway

Answer 16

transduction –> transmission (in sensory afferents)–> modulation –> perception

Question 17

3 major classes of opioid receptors**

Answer 17

mu, kappa, delta

Question 18

most opioid receptors are stimulation by ____ and blocked by ____**

Answer 18

morphine (agonist), naloxone (antagonist)

Question 19

most common cause of death from opioids in humans***

Answer 19

ventilatory depression

Question 20

opioid receptors are highly species dependent

Answer 20

:)

Question 21

where are highest densities of opioid receptors?

Answer 21

brain, spinal cord, GI tract

Question 22

major effects of opioid receptor stimulation

Answer 22

• analgesia
• resp. depression
• nausea
• GI stasis
• CV depression

Question 23

“gut-brain” peptides

Answer 23

diverse group of peptides that are most prevalent in CNS and GI tissues. 1ary endogenous substances that activate opioid receptors. Include enkephalins, endorphins, dynorphins, and endomorphins

Question 24

roles of endogenous opioid peptides

Answer 24

• response to painful stimuli, etc.
• acupuncture
• laser therapy

Question 25

analgesia is most effective against what type of pain?

Answer 25

dull, constant pain.

Question 26

where do opioids modulate pain?

Answer 26

``` spinal cord (dec. substance P release) brain ```

Question 27

opioids in cats often mixed with ___. Why??

Answer 27

ketamine. Cats can become aggressive, hyperresponsive to opioids

Question 28

opioids in horses often mixed with:

Answer 28

xylazine

Question 29

hallmark of opioids***

Answer 29

marked species differences!

Question 30

are opioids additive with other CNS depressants?

Answer 30

yes

Question 31

how can ventilatory depression from opioids be reversed?

Answer 31

naloxone

Question 32

how is nausea stimulated from opioids?

Answer 32

-stim. of brainstem chemoreceptor trigger zone (CTZ)

Question 33

CNS actions of opioids

Answer 33

- analgesia - sedation - ventilatory depression - nausea/emesis - cough suppression - pupillary constriction - mood alterations - tolerance and physical dependence - neuroendocrine effects (i.e. increased ADH release)

Question 34

GI actions of opioids

Answer 34

-GI stasis

Question 35

CV actions of opioids

Answer 35

(unwanted side effects) - CV depression - can be reversed by anti-cholinergic agents

Question 36

side effects of opiods*

Answer 36

- depend on agent, dose/route of admin, and species - depressed ventilation - sedation/excitation - constipation - parasymp. actions - CV depression - M. rigidity

Question 37

signs of opioid toxicity

Answer 37

- depressed ventilation - pinpoint pupils - coma

Question 38

contraindications for opioid use**

Answer 38

- large animal, felines - pregnancy - shock/CV dysfunction - closed head injury - pulmonary dysfx

Question 39

opioid drug interactions**

Answer 39

- oral admin. - ALL CNS depressants** - breathing pure O2 - cholinergic drugs or AChe

Question 40

chars. of morphine**

Answer 40

- prototype opioid agonist - opium-derived alkaloid - class 2** - act on all opiate receptors - slowly crosses BBB - relatively high first pass metabolism with fairly slow GI absorption**

Question 41

how is morphine metabolized?**

Answer 41

via glucuronide conjugation

Question 42

chars. of naloxone**

Answer 42

- prototype opioid antagonist - relatively short half-life, so must keep giving*** - reversal agent for opioid intoxication

Question 43

Most opioids are DEA class ___

Answer 43

II

Question 44

butorphanol is DEA class__

Answer 44

IV

Question 45

DEA class I drug def.

Answer 45

Schedule I drugs, substances, or chemicals are defined as drugs with no currently accepted medical use and a high potential for abuse. Schedule I drugs are the most dangerous drugs of all the drug schedules with potentially severe psychological or physical dependence.

Question 46

DEA class II drug def.

Answer 46

drugs with a high potential for abuse, less abuse potential than Schedule I drugs, with use potentially leading to severe psychological or physical dependence. These drugs are also considered dangerous.

Question 47

DEA class III drug def.

Answer 47

drugs with a moderate to low potential for physical and psychological dependence. Schedule III drugs abuse potential is less than Schedule I and Schedule II drugs but more than Schedule IV.

Question 48

DEA class IV drug def.

Answer 48

drugs with a low potential for abuse and low risk of dependence.

Question 49

DEA class V drug def.

Answer 49

drugs with lower potential for abuse than Schedule IV and consist of preparations containing limited quantities of certain narcotics. Schedule V drugs are generally used for antidiarrheal, antitussive, and analgesic purposes.

Question 50

fentanyl has more/less CV impact than morphine

Answer 50

less. However, it is 100x more potent than morphine for most indications!

Question 51

buprenorphine DEA class __

Answer 51

III

Question 52

neuroleptanalgesia

Answer 52

drug-induced condition in which the animal is unresponsive to sensory stimuli and shows no response to pain but is NOT completely unconscious. - produced by combo of neuroleptic agent (DA antagonist, which prevents m. rigidity) with opioid analgesic - produces additive CNS depression

Question 53

T/F: it is more common for sedative/opioid combinations to be used in hospital setting than neuroleptic/opioid combos**

Answer 53

T