Opioids Flashcards

1
Q

where do opioids come from

A

opium poppy seed pod juice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what 3 main drugs does opium contain

A

heroin, codeine, morphine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the difference between opiate and opioid

A

opiate = any natural component of opium
opioid = any natural or synthetic derivative of opium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

why do we give opioids as pre-meds

A

because general anesthetics do not inhibit pain signal generation, so a painful stimulus during a procedure could transmit enough pain signals to the RAS to awaken the patient - giving an opioid prevents pain signal generation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

where are opioid receptors present

A

pain pathways and in most other organ systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

T/F mammals produce endogenous opioids

A

T

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what 5 uses are opioid drugs used for

A

1) analgesia
2) cough suppression (antitussive)
3) sedation
4) treatment of diarrhea
5) emesis (apomorphine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are the opioid receptor families that cause:
- immediate analgesia
- dysphoria

A

immediate analgesia:
- Mu
- Delta
- Kappa

dysphora:
- Sigma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the mechanism of action of opioids on pre-synaptic receptors

A

mu, delta, kappa receptors inhibit Ca entry, which inhibits NT release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the mechanism of action of opioids on post-synaptic receptors

A

mu receptors open K channels, which causes hyperpolarization and inhibits APs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are the effects of mu opioid receptor stimulation (4)

A
  • intense analgesia
  • euphoria
  • miosis or mydriasis
  • respiratory depression (dose-dependent)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the effects of delta opioid receptor stimulation (4)

A
  • analgesia
  • respiratory depression, not as intense as mu
  • protection from hypoxic injury
  • hibernation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the effects of kappa opioid receptor stimulation

A
  • moderate analgesia
  • no respiratory depression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the effects of sigma opioid receptor stimulation

A
  • dysphoria
  • hallucinations
  • respiratory and vasomotor stimulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what can stimulate sigma receptors

A

opioids and some non-opioids such as ketamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the 3 properties of opioid stimulation (i.e. what are the 3 ways that opioids can act on opioid receptors)

A

1) full agonist
2) partial agonist/antagonist
3) mixed agonist/antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how does fentanyl act on opioid receptors (and which ones)

A

full mu agonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

how does butorphenol act on opioid receptors (and which ones)

A

mu partial agonist/antagonist and kappa agonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

T/F if you have a patient that presents with severe pain, you should first give a weaker opioid such as butorphanol and then give a stronger opioid such as fentanyl if pain persists

A

F; if you do this the butorphanol will block the effects of fentanyl by acting as a partial agonist/antagonist on the mu receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what two drugs are mu partial agonists/antagonists

A

butorphanol and buprenorphine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is the difference between buprenorphine and butorphanol

A

both are mu partial agonists/antagonists, butorphanol is a kappa agonist whereas buprenorphine is a kappa antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are the 5 main analgesic opioids

A

1) morphine
2) hydromorphone
3) fentanyl
4) butorphanol
5) buprenorphine

23
Q

what is the main anti-diarrheal opioid

A

loperamide

24
Q

what is the main antitussive opioid

A

butorphanol

25
Q

what is the main emetic opioid

A

apomorphine

26
Q

what opioids are used for chemical immobilization

A

1) etorphine
2) carfentanyl

27
Q

what is the duration of analgesia of hydromorphone

A

3-6h

28
Q

what is the duration of analgesia of buprenorphine

A

4-8h

29
Q

what is the analgesic potency of fentanyl relative to morphine

A

100x

30
Q

are opioids weak acids or weak bases

A

bases

31
Q

what is the metabolism of opioids

A

phase I and II metabolism with high first-pass effect

32
Q

T/F codeine has a high analgesic effect in dogs because it gets metabolized to morphine

A

F

33
Q

In regards to full mu agonists:
- sedation is most likely in _________
- excitement is likely in __________

A
  • dogs and primates
  • most other species
34
Q

high doses of morphine cause what in cats; what drug does not do this

A

excitement - called sham rage;

not seen with hydromorphone

35
Q

what can morphine trigger but not fentanyl or hydromorphone

A

histamine release -> hypotension

36
Q

death from opioid overdose is due to

A

respiratory arrest -> due to respiratory depression (mu effect)

37
Q

what do we use to reverse opioid overdose

A

naloxone

38
Q

what effects to opioids have on the gastrointestinal tract

A
  • increase segmentation but reduce propulsion -> constipation
  • bile sphincter constriction -> biliary colic
  • nausea and vomiting
39
Q

what is the effect of opioids on the urogenital system

A
  • increases bladder sphincter and detrusor muscle tone
  • slows uterine contractions and inhibits birth reflexes
40
Q

T/F fentanyl can be used as an analgesic + sedative prior to induction

A

T

41
Q

overdose of fentanyl causes

A

seizures

42
Q

how is fentanyl commonly administered

A

patch

43
Q

etorphine is _______ more potent than morphine and carfentanyl is _____ more potent than morphine

A

4000x; 10,000x

44
Q

what is the reversal agent for carfentanyl and etorphine (M99)

A

diprenorphine (M50/50)

45
Q

the main beneficial effect of buprenorphine is via stimulation of what receptor

A

kappa receptor stimulation

46
Q

T/F butorphanol is commonly used for post-op analgesia

A

T

47
Q

how is buprenorphine administered in cats

A

IM; transmucosal at home

48
Q

how is buprenorphine absorbed

A

transmucosally

49
Q

what is the main advantage of buprenorphine

A

at home administration to animals with chronic pain

50
Q

how is apomorphine given

A

in the eye

51
Q

how does apomorphine trigger vomiting

A

dopamine receptors

52
Q

T/F vomiting from apomorphine administration can be stopped by giving naloxone

A

F

53
Q

how does naloxone work

A

inhibits mu receptors

54
Q

T/F naloxone can be used to treat circulatory shock

A

T