Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

NBB1 > Opioid Pharmacology > Flashcards

Opioid Pharmacology Flashcards

(93 cards)

Start Studying
1
Q

What’s the difference between an opiate and an opioid?

A

Opiate: naturally occurring
Opioid: any natural, synthetic or semi-synthetic compound

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

What is an alkaloid?

A

a class of naturally occurring organic-nitrogen containing bases

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

How do we classify opioids?

A
  1. Interaction with opioid receptor subtypes: mu, kappa, delta
  2. Intrinsic activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What type of receptors are opioid receptors?

A
  • all are G-protein coupled receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 3 levels of intrinsic activity of opioids?

A

Pure agonists, pure antagonists and mixed agonist-antagonists

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

How can we characterize mixed agonist-antagonists?

A

Kappa agonists: produce analgesia

Mu antagonists: interfere with morphine, heroin

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

What are the endogenous opioid peptides?

A

endorphins, enkephalins, dynorphins

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

Where are opioid peptides located and what is their function?

A

Brain: NTs and neuromodulators

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

What is the function of endogenous opioid peptides?

A

Modulate pain transmission in spinal cord

Alter acetylcholine release in GI myenteric plexus

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

Where do beta-endorphins come from?

A

Cleavage product of POMC, precursor hormone for ACTH

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

What are the acute effects of opioids?

A 
analgesia
respiratory depression
euphoria
cough suppression
miosis
constipation
increased IC pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the chronic effects of opioids?

A

tolerance

physical dependence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the special acute effect of meperidine/demerol?

A

mydriasis (pupil dilation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a one difference between opioid types with regard to acute effect?

A

histamine release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is clinical selection of an opioid based on?

A

Pharmacokinetics

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

What is the main use of opioids in the clinic?

A

1 Analgesia for moderate to severe pain (morphine/heroin)
2 Analgesia for moderate long-term chronic pain (oxycodone or hydrocodone)
3 Anesthesia (fentanyl)
4 cough suppressant (dextromethorphan/codeine)
5 diarrhea relief (diphenoxylate or loperamide, decreased BBB penetration)
6 acute pulmonary edema (morphine)

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

What is the most important use of morphine today?

A

myocardial infarction

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

When are opioids contra-indicated?

A

head injuries

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

What do you use if a cancer patient becomes tolerant to morphine?

A

fentanyl IM/IV

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

How do opioids act centrally for analgesia/mood?

A

inhibit transmission and processing of pain signals (emotional response altered in limbic cortex)

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

How do opioids act peripherally for analgesia/mood?

A

On sensory neurons, particularly helpful for patient’s with tissue inflammation and nerve ending damage

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

What are the clinical characteristics of opioids?

A

Selective analgesia without hypnosis, sedation or impaired sensation
Mood elevation or euphora can occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What types of pain are best treated by opioids?

A

Prolonged burning pain (vs. sharp pain of incision)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What type of pain is NOT helped by opioids?

A

Neuropathic pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the mechanism of euphoria created by opioids?
Suppress the release of GABA, which stimulates dopamine release in a neighboring neuron
26
What are the side effects of opioids experienced in the CNS?
Drowsiness, heaviness, difficulty concentrating | Sleep
27
Why are opioids contra-indicated in head injury?
1 may exacerbate damage caused to the respiratory center in brain 2 nausea, miosis and CNS clouding caused by opioids can confuse the neurologic eval
28
How do opioids induce respiratory depression?
- Directly affect respiratory centers in medulla causing decreased sensitivity to increasing blood levels of CO2 - increased CO2 causes cerebral vasodilation --> increased IC pressure
29
What is the major toxicity of opioids?
Respiratory depression - almost always cause of death from overdose
30
How does sleep affect the response to CO2?
Depresses the response, potentiates opioid effect
31
How does dose affect respiratory depression?
Effects are dose-related. Very large doses can cause apnea
32
Are respiratory depression and analgesia interlinked?
YES. Direct correlation, hard to reverse depression w/o losing analgesic effects
33
How do opioids suppress cough?
Depression of cough centers in the medulla (different mechanism from analgesia/resp. depression)
34
What type of opioids suppress cough? Do they have analgesic activity?
d-isomers of opioids, and no
35
What are the 2 agents that suppress cough?
Codeine or dextromethorphan
36
How do opioids constrict pupils?
Stimulation of Edinger-Westphal (PSNS) nucleus of CN III
37
What is a telltale sign of opioid overdose?
Miosis
38
How can we reverse opioid overdose?
Naloxone, atropine or ganglionic blockers (mecamylamine)
39
How do opioids induce nausea and vomiting?
Stimulate the chemoreceptor trigger zone to activate the vomiting center
40
Which population is most likely to vomit from opioids?
Ambulatory patients vs. supine because emetic effects are potentiated by stimulation of the vestibular apparatus
41
How do opioids affect skeletal muscles?
large IV doses may cause stiffness of skeletal muscle
42
What is the mechanism of the effect in skeletal muscle?
mu-mediated increase in striatal dopamine synthesis and inhibition of striatal GABA release
43
Which opioid is most likely to cause skeletal muscle stiffness?
Fentanyl
44
How do opioids affect HR? Mechanism?
Cause bradycardia by stimulation of central vagal nerve
45
What other CV effects result from opioid use?
Decreased sympathetic tone --> vasodilation, orthostatic hypotension
46
Which opioids cause histamine release? What are the downstream effects?
Morphine, fentanyl and merperidine | Vasodilation and hypotension
47
What are side effects of histamine release? Is this an allergy?
Skin redness, urticaria (hives/rash) and pruritis (itchy skin) NO
48
What is the mechanism of constipation?
Spasm of smooth muscle in GI tract Diminished rhythmic propulsive activity (peristalsis) Delayed gastric emptying
49
What opioids are used for diarrhea? Why are they good?
Diphenoxylate and loperamide | Poorly CNS-absorbed
50
How do opioids affect the biliary system?
Contract smooth muscle along biliary tree, spasm the spinchter of Oddi May precipitate biliary colic (gall stones)
51
How can we antagonize the effects on the biliary system?
Naloxone | Partially reversed by glucagon, nitroglycerin or atropine
52
How do opioids affect the urinary tract?
Anti-diuretic --> urinary retention
53
How are opioids used in pregnancy?
Sometimes used sparingly - relieve labor pain
54
What are concerns with opioids used in pregnancy?
- Cross the placenta - may cause resp. depression in baby | - Chronic use in utero may cause physical dependence and subsequent neonatal withdrawal after delivery
55
How does tolerance develop over time?
Adaptive response of AC and/or G protein coupling (Not a PK effect)
56
How does tolerance develop w/ respect to other opioids?
Additively!
57
What is the order of effects to which patients become tolerant?
Rapidly: depressant: analgesia, resp. depression, euphoria | More slowly: stimulatory effects: miosis, constipation
58
How can we apply the differential tolerance mechanisms to a) heroin addicts?
A) heroin addicts/methadone patients: - Little euphoria from high doses - still get constipation/miosis
59
How can we apply the differential tolerance mechanisms to b) cancer patients?
B) terminal cancer patients requiring high doses for analgesia - tolerant to respiratory depression - require laxatives for constipation
60
When does withdrawal occur?
Withdrawal or abstinence syndrome occurs when the drug is stopped = physical dependence
61
How do you stop withdrawal?
Give a small dose of opioid
62
What does giving antagonist to a physically dependent person do?
Causes rapid onset of more severe withdrawal syndrome
63
What are the symptoms of withdrawal?
sweating, runny nose, vomiting, diarrhea, piloerection (goose bumps), mydriasis, shaking chills, drug seeking behavior
64
What is the difference between physical dependence and psychological dependence?
Physical: natural need for higher dose of analgesia | Psychological dependence: addiction, craving a high
65
What is methadone used for?
Long-acting opioid used for detox to wean an addicted individual off of morphine, heroin, etc.
66
What are the properties of methadone?
- Longer half life (24-35 hours)
67
What are the withdrawal effects of methadone?
- Withdrawal effects: protracted, but milkd
68
How does one taper off of methadone?
Must be tapered slowly to avoid risk of acute withdrawal, craving, abuse
69
What are the benefits of methadone?
1 Intensity of withdrawal symptoms decreased (also drug seeking/illegal activity) 2 Tolerance develops to opioid euphoria - so injection of heroin is not reinforcing 3 ORAL - no needle use 4 obtaining methadone requires regular contact to caregivers, access to counseling
70
What is the classic triad of opioid overdose?
miosis apnea stupor (coma)
71
What is the defining symptom of opioid overdose?
Respiratory depression
72
What is a later clinical manifestation of opioid overdose?
Pulmonary edema
73
When do seizures occur with overdose?
Only occasionally, with mperidine, pentazocine/naloxone
74
What are the PK of morphine?
- Rapid absorption, wide distribution, rapid hepatic clearance (70% first pass metabolism) - Hydrophilic: CNS penetration/exit are slow = slow onset and long duration
75
How is heroin different than morphine w/ regard to PK?
Heroin: more lipophilic --> faster CNS penetration! Morphine: hydrophobic
76
What are the PK of fentanyl?
- Rapid absorption, wide distribution, short T1/2 (>60% first pass metabolism) - Lipophilic - rapidly crosses BBB - Multiple delivery routes
77
Which is more powerful, morphine or fentanyl?
Fentanyl: 80-100 times more powerful
78
What considerations are there for dosing opioids?
- Requirements vary per patient | - Narrow therapeutic window
79
Who should receive lower doses of opioids?
``` Elderly hypovolemic debilitated hypothyroid those taking CNS depressants ```
80
Which two opioids that include acetaminophen?
Vicodin: hydrocodone / acetaminophen Percocet: oxycodone/ acetaminophen
81
What is important to monitor in acetaminphen/opioid combinations?
- Limit acetaminophen to
82
How is naloxone administered?
IV or IM
83
How is naltrexone administered?
orally
84
What is the goal of naloxone?
To reverse opioid overdose, including resp. depression
85
What are side effects of naloxone?
May induce withdrawal
86
What is the goal of naltrexone?
Used for maintenance therapy and relapse prevention
87
What is the goal of opioid partial agonists or mixed agonist-antagonists?
To find drugs with: - less abuse potential - decreased respiratory depression
88
What is the action of opioid partial agonists or mixed agonist-antagonists?
- Analgesic properties | - Antagonize morphine effects
89
How does Buprenorphine work?
partial agonist at mu receptor
90
What is the goal of Buprenorphine? What is the formulation?
- maintenance therapy for opioid/alcohol dependence when added to naloxone
91
What are are the mixed agonist-antagonists?
nalorphine pentazocine nalbuphine butorphanel
92
What is the action of mixed agonist-antagonists?
Act as kappa agonists to produce analgesia, also mu antagonists
93
What is a caution of mixed agonist-antagonists?
Also mu antagonists, so can induce acute withdrawal in heroin or morphine addicts

NBB1 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions