Opioid, Opioid agonist/antagonist, antagonist Factoids Flashcards Preview

Pharm 512 Drugs > Opioid, Opioid agonist/antagonist, antagonist Factoids > Flashcards

Flashcards in Opioid, Opioid agonist/antagonist, antagonist Factoids Deck (83):
1

What is the potency ratio of Sufentanil?

500-1000

2

How do opioids provide analgesia through the CNS?

Inhibiting the ascending transmission of nociceptive transmission from the spinal cord AND activate pain control pathways from the midbrain

3

What is the prototype opioid drug?

Morphine

4

What is the potency ratio of Alfentanil?

10-20

5

What opioid receptor has the largest concentration?

The Mu receptor has the largest concentration in the cerebral cortex, limbic system, caudate putamen, thalamus, periaqueductal grey matter and pre/post synaptic neurons in the spinal cord.

6

Where is the highest concentration of Mu receptors?

Periaqueductal Grey Matter

7

What is the potency ratio of Butorphanol (Stadol)?

5

8

What cardiovascular effects do opioids have?

Bradycardia with little effect on blood pressure and dose dependent peripheral vasodilation.

9

What is the most stimulating part of surgery?

Intubation, which means you need more drugs up front.

10

What is the active metabolite of morphine and in what instance should Morphine use be avoided?

Morphine-6-Glucuronide (M6G) is the active metabolite that prolongs Morphines effects. It should be avoided in renal patients due to decreased elimination.

11

What is the potency ratio of Codeine?

0.4

12

What is an undesirable quality of Morphine?

Histamine release, it should be avoided in asthmatics and hemodynamically unstable patients.

13

What is the metabolite of Meperidine (Demerol) and what's its disadvantage?

Normeperidine - lowers seizure threshold

14

What drug potentiates muscle rigidity in Remifentanyl use?

Nitrous Oxide, most significantly seen with chest wall compliance and truncal rigidity.

15

What is the major benefit to Dilaudid?

There is no known active metabolite, good for use in renal patients.

16

What opioid receptor reduces shivering, and causes dysphoria, sedation mitosis and analgesia?

Kappa Receptors

17

What is the potency ratio of Fentanyl and Remifentanyl?

100

18

What is unique about Fentanyl's metabolism?

Fentanyl undergoes significant 1st pass effect in the lungs, however clearance is dependent on hepatic blood flow.

19

Why isn't Alfentanil widely used?

There is great patient to patient variability, not very predictable.

20

What is the potency ratio of Buprenorphine?

30

21

How is Remifentanyl metabolized?

Metabolized by non-specific blood esterases (be aware when giving to patient with cholinesterase deficiency)

22

What can occur in a chronic drug user when given pain medication?

Down regulation of one receptor causes use of another receptor that isn't as effective. May have to give more medication to alleviate pain.

23

What opioid agonist-antagonist has the same potency as Morphine?

Nubaine

24

How do opioids effect the eyes?

Parasympathetic stimulation of the oculomotor nerve causes vasoconstriction this is known as Miosis (small pupils)

25

What is the most potent phenylpiperidine?

Sufentanil

26

Meperidine (Demerol) use is contraindicated with which drug class?

MAOI, significant reaction and possible seretonergic crisis

27

What is the potency ratio of Meperidine (Demerol)?

0.1

28

Why aren't opioids considered anesthetics?

Opioids do not provide amnesia and the patient will have recall if not given another medication

29

Where are Kappa receptors located in the CNS?

Nucleus raphe mangnus (midbrain)
Hypothalamus
Spinal Cord

30

Which opioid receptor provides analgesia, mild constipation, urinary retention, and dependence?

Delta Receptors

31

if a patient is not intubated, how can opioids effect ICP?

Opioids can increase ICP by hypoventilation which causes vasodilation and increased cerebral blood flow

32

What are the effects of stimulating the Mu opioid receptor?

Analgesia, euphoria, sedation, dependence, respiratory depression, miosis, marked constipation, urinary rentention, bradycardia, pruritus, muscle rigidity and biliary spasm

33

Where are Delta opioid receptors located in the CNS?

Olfactory centers
Cerebral cortex
Nucleus accembens
Caudate putmen
Spinal Cord

34

True or false, respiratory depression is a very sensitive indicator of opioid effects?

False, respiratory depression is NOT a very sensitive indicator of opioid effects. (the respiratory drive is separate from analgesia)

35

How do opioids effect the respiratory system?

Opioids produce dose dependent depression of ventilatory response of CO2 by directly affecting the ventilatory centers in the medulla.

36

What cardiovascular mechanisms are not effected by opioid agents?

Opioids have no effects on myocardial contractility, baroreceptor reflexes and autonomic responsiveness.

37

What causes generalized hypertonus that is associated with high dose opioids?

Mu receptors and dopamine and GABA pathways

38

What drugs can relieve the muscle rigidity associated with opioids?

Relieved by muscle relaxants and antagonists (succinylcholine)

39

What is the least lipophilic opioid agent?

Morphine

40

Why is Codeine thought to be a weak opioid?

10% is converted to morphine

41

What opioid is structurally similar to atropine?

Meperidine (Demerol) has antispasmodic properties

42

What opioid can be given post operatively to reduce shivering?

Meperidine (Demerol), works at the Kappa receptors

43

What opioid is the most lipid soluble?

Sufentanil

44

Why shouldn't we bolus Remifentanil?

Increased risk for muscle rigidity, limits bolus dosing

45

What opioid can not be used in an epidural?

Remifentanil, it causes glycine neurotoxicity

46

Define Agonist

Drugs that occupy a receptor and activate them

47

Define Antagonist

Drugs that occupy receptors but do not activate them, antagonists block receptor activation by agonists.

48

How do antagonists, agonists and partial agonists effect their receptor sites?

Agonists exhibit unlimited effect
partial agonists reach maximum effect after specific dose
True antagonists never exhibit the clinical effect

49

What types of drugs have a ceiling effect?

Partial agonists

50

What does a steep dose response curve indicate?

The drug is more responsive with higher doses, small changes in dose produce large effects

51

Which drug's antagonistic affects relates to its ability to displace opioid agonists from their receptors?

Buprenorphine

52

Which receptor site does Buprenorphine compete for?

Mu

53

Which antagonist-agonist opioid is an agonist at the Kappa receptor and a weak antagonist at the Mu receptor?

Butorphanol

54

Why aren't we as worried about respiratory depression in opioid agonist-antagoinist agents?

Respiratory depression exhibits a ceiling effect in opioid agonist-antagoinist agents

55

What factors should be considered if you are using an agonist-antagonist as a primary analgesic?

Consider the options for rescue or further treatment of pain

56

What is a non-selective antagonist at all opioid receptors?

Naloxone, treats opioid induced respiratory depression, pruritus and suspected drug overdose

57

How should Naloxone be administered?

Naloxone should be given in small incremental doses because it can cause flash pulmonary edema.

58

Which opioid antagonist has an active metabolite?

Naltrexone

59

Which agonist antagonist opioid agent causes an increase in cardiovascular effects and why?

Butorphanol causes an increase in circulating catecholamines

60

Which partial opioid agonist is very slow to dissociate from the opioid receptor?

Buprenorphine, there is not a rescue drug for this, should be used with caution

61

Where is nociception suppressed in neuraxial opioids?

Lamina II and V cells of the dorsal horn of the spinal cord and Kappa receptors in the substantia gelatinosa

62

What two side effects are seen more in neuraxial opioids than if the opioid was given IV?

Greater incidence of pruritus and urinary retention

63

What is the difference between spinal anesthesia and an epidural?

Spinal anesthesia is injected into the CSF on the spinal cord where an epidural is placed in the potential space

64

What three factors determine opioid uptake from neuraxial anesthesia?

Epidural fat
CSF
Systemic circulation of blood

65

Why is it beneficial to add epinephrine to a neuraxial opioid?

Epi constricts the vessels decreasing blood flow and keeping the medication in the the affected area longer

66

What two opioid agents are associated with early respiratory depression in neuraxial anesthesia?

Fentanyl and Sufentanil ( <2 hrs) central circulation

67

What opioid agent is associate with delayed respiratory depression in neuraxial anesthesia?

Morphine ( >2hrs) ventral medulla

68

What determines how fast or slow an opioid will take effect in neuraxial anesthesia?

Dependent on the lipid solubility of the drug

69

What is the major cause of respiratory depression in neuraxial anesthesia?

Additional medication given because time was not allowed for epidural/spinal to work

70

What is the intrathecal or subarachnoid single dose of Fentanyl?

5-25 mcg

71

What is the intrathecal or subarachnoid single dose of Morphine?

0.1-0.3 mg

72

What is the epidural single dose of Fentanyl?

50-100mcg

73

What is the epidural single dose of Morphine?

1-5mg

74

What is the epidural continuous infusion of Fentanyl?

25-100mcg/hr

75

What is the epidural continuous infusion of Morphine?

0.1-1mg/hr

76

What is the onset and duration of Alfentanil in comparison to fentanyl?

Alfentanil has a more rapid onset and a shorter duration of action than fentanyl.

77

What type of surgery would warrant the use of Nalbuphene (Nubain) for post-operative pain management?

Brain surgery! Because it reverses sedative qualities.

78

Why is continuous monitoring important after a dose of Narcan is given?

Because of its short half-life in comparison to opioids, respiratory depression may return once Narcan wears off.

79

Which opioid agonist-antagonist is useful in the cardiovascular population?

Nalbuphine (Nubian)

80

What adverse effects does Naloxone have on the body?

Nausea and Vomiting
Increased SNS activity
Pulmonary edema
Sudden death

81

What drug is often given to drug addicts to prevent the euphoric effects of the drug they abuse?

Naltrexone

82

Why is the SNS unable to be activated during neuraxial opioid administration?

SNS is inhibited due to blockage of the sympathetic chain ganglia

83

Where can neuraxial opioids be given?

Can be given via epidural and intrathecal routes