PHARMACOLOGY | Opioid Flashcards
How long does it take for a fentanyl patch to reach maximum plasma concentration?
A. 30 hours
B. 15 hours
C. 10 Hours
30 hours
Which of the following receptor is responsible for the RESPIRATORY DEPRESSION effect of opioid:
A. Mu-2
B. Mu-1
C. Kappa
D. Delta
mu-2 receptors
O2 dissociation curve in Opioid administration:
A. shift to the RIGHT
B. shift to the LEFT
C. Neither
curve shift to THE RIGHT
The RESPIRATORY DEPRESSION induced by OPIOID is caused by:
A. Increasing the CO2 apneic threshold in the medulla
B. Supraspinal mechanism
C. Peripherally mediated
INCREASING the CO2 apneic threshold in the MEDULLA
TRUE or FALSE
The context-sensitive halftime for REMIFENTANIL is independent of the duration of infusion.
The context-sensitive halftime of REMIFENTANIL is 4 MINUTES
TRUE
One of the clinical effect of Opioid is EPILEPTOGENIC due to Leu-enkephalin and B-endorphin agonism.
What receptor is involved in this process?
A. Mu
B. Kappa
C. Delta
delta receptors
Mu 1 receptors associated side effect?
EUPHORIA
Urinary Retention
Mu 2 receptors associated side effects?
Hypoventilation
Constipation
Physical Dependence
Kappa receptors associated side effects
Dysphoria
Hallucinations
Opioid effect that DO NOT show tolerance
A. Mydriasis
B. Dysphoria
C. Euphoria
D. Miosis
MIOSIS
Miosis and Constipation are the ONLY two spared from tolerance!
TRUE or FALSE
Remifentanil metabolism in infants is faster compared with that of Adults
TRUE
Equianalgesic of IV Morphine to PO
10mg IV = 30mg PO
Which narcotic has a local anesthetic activity?
A. Meperidine
B. Butorphanol
C. Methadone
D. Alfentanil
MEPERIDINE
Meperidine shares several structural features that are present in local anesthetics including a tertiary amine, an ester group, and a lipophilic phenyl
group.
Indeed, meperidine administered intrathecally blocks sodium channels
to a degree comparable with lidocaine and can be used to provide surgical
anesthesia.
STOELTING | 8th edit
Narcotic effects that are not REVERSED by NALOXONE
Nausea/Vomiting
Constipation
MUSCLE RIGIDITY
PAIN receptor sites in the brain
AMYGDALA
PERI-AQUEDUCTAL GRAY
SOMATOSENSORY CORTEX (Locus Ceruleus & Rostral Ventral Medulla)
Dull “Burning” Pain is:
UNmyelinated C Fibers
Sharp “Pin prick” Pain is:
MYelinated A-delta FIBERS
Depression of ventilation is due to what receptor?
A. Mu-2
B. Mu-1
C. Kappa
Mu-2
This is due to the BRAINSTEM involvement at the Mu-2 receptors
True of HYDROMORPHONE except:
A. The active metabolite hydromorphone-3-glucuronide has no analgesic properties but may cause neuroexcitation.
B. Peak effect is 15 mins
C. Equianalgesic of IV to PO is 1.5mg to 7.5mg
D. Used as a post-operative pain management due to its very short duration
D. Used as a post-operative pain management due to its very short duration
It has a long duration.
PURE OPIOID ANTAGNONISTS
Naloxone
Naltrexone
Nalmefene
These are ALL pure Mu opioid receptor antagonists with no agonist activity!
Stoelting | 6th Edit
True of NALOXONE except:
A. Is a nonselective antagonist at all three opioid receptors
B. Facilitate treatment of deliberate opioid overdose, and detect suspected physical dependence
C. Duration of action of naloxone (30 to 45 minutes) is presumed to be due to its rapid removal from the brain
D. Naloxone cannot easily cross the placenta
E. Administration of naloxone to an opioid-dependent parturient may produce acute withdrawal in the neonate
D. Naloxone cannot easily cross the placenta
Receives inputs from Ag and C primary afferent fibers
LAMINA - I
receives input primarily from LARGE diameters AB fibers from skin
Lamina IV - V
45
AGONIST-ANTAGONIST Opioid
Pentazocine
Bremazocine
Dezocine
Maptazinol
Butorphanol
Buprenorphine
Nalorphine
NALBUPHINE
OPIOID Full ANTAGONIST
Naloxone
Naltrexone
Nalmefene
Naloxone and naltrexone are pure μ-opioid receptor antagonists with no agonist activity.
In the brain, opioid receptors are primarily found in:
Periaqeuductal gray
Locus Ceruleus
Rostral ventral medulla
The effect-site equilibration time(its time to PEAK analgesia) of fentanyl is:
A. 6.8 minutes
B. 3.5 minutes
C. 2.5 minutes
D. 5 minutes
The onset of CNS effects of Sulfentanil(effect-site equilibration time of 6.2 minutes is similar to that of 6.8 minutes for fentanyl)
Which of the following opioids has the longest context-sensitive halftime?
A. Fentanyl
B. Remifentanil
C. Sulfentanil
D. Alfentanil
Fentanyl
FROM LONGEST TO SHORTEST
F>A>S>R
Fentanyl > Alfentanil > Sulfentanil > Remifentanil
The effect-site equilibration time(its time to PEAK analgesia) of Alfentanil is:
A. 10 minutes
B. 2.5 minutes
C. 1.4 minutes
D. 5 minutes
C. 1.4 minutes
A unique advantage of alfentanil compared
with fentanyl and sufentanil is the more rapid onset of action (rapid effectsite equilibration) after the IV administration of alfentanil.
For example, the effect-site equilibration time for alfentanil is 1.4 minutes compared with 6.8
and 6.2 minutes for fentanyl and sufentanil, respectively.
Activation of opioid receptors leads to activation of
which intracellular transduction mechanism?
(A) G proteins
(B) adenylate cyclase
(C) voltage gated calcium channels
(D) voltage gated sodium channels
(E) outward recti ying potassium channels
(A) G proteins
G proteins (Gi and/or Go) are activated, as are inward rectifying potassium channels. Adenylate cyclase and voltage-gated calcium channels are inhibited by activation of the opioid receptor.
Voltage-gated sodium channels ARE NOT involved in opioid receptor-activated intracellular transduction mechanisms.
Which of the following opioids is the most hydrophilic?
(A) morphine
(B) fentanyl
(C) codeine
(D) methadone
(E) heroin
(A) morphine
Morphine has a relatively low lipid solubility.
Fentanyl, codeine, methadone, and heroin are all more lipophilic than morphine.
An adult is administered a single dose o entanyl
(100 micrograms intravenously). The clinical effects
of fentanyl are terminated mainly by:
(A) redistribution
(B) hydroxylation
(C) N-dealkylation
(D) conjugation
(E) demethylation
(A) redistribution
After a small bolus of fentanyl the plasma and CSF
levels of fentanyl rapidly diminish due to redistribution to muscle and at. Fentanyl undergoes N-dealkylation and hydroxylation in the liver.
Which opioid has the longest duration of action
after epidural injection?
(A) alfentanil
(B) fentanyl
(C) hydromorphone
(D) methadone
(E) morphine
(E) morphine
Morphine is relatively hydrophilic compared to the
other listed opioids.
This means morphine will remain in the CSF or a longer period of time—up to 24 hours after a single bolus.
What is the correct order of the following opioids in regards to lipophilic properties, from most to least lipophilic?
A. Morphine—Remifentanil—Alfentanil—Sufentanil
B. Sufentanil—Fentanyl—Alfentanil—Morphine
C. Remifentanil—Alfentanil—Fentanyl—Sufentanil
D. Sufentanil—Remifentanil—Alfentanil—Fentanyl
E. Sufentanil—Morphine—Fentanyl—Remifentanil
B. Sufentanil—Fentanyl—Alfentanil—Morphine
TRUE or FALSE
The clonidine is more effective than meperidine in reducing postoperative shivering
TRUE
This opioid antagonist is primarily used for Alcohol dependence:
A. Naloxone
B. Naltrexone
C. Nalmefene
C. Nalmefene
Nalmefene is an opioid antagonist primarily used for alcohol dependence and other addictions but could counteract full agonist opioids used for surgery.
___ is a nonselective antagonist at all three opioid receptors:
A. Naloxone
B. Naltrexone
C. Nalmefene
A. Naloxone
Which of the following is CORRECT regarding the indication of NALOXONE?
A. Treat opioid-induced depression of ventilation as may be present in the postoperative period
B. Treat opioid induced depression of ventilation in the neonate due to maternal
administration of an opioid
C. Facilitate treatment of deliberate opioid
overdose
D. Detect suspected physical dependence
E. All are CORRECT
E. All are CORRECT
Naloxone is selective when used to:
(1) treat opioid-induced depression of ventilation as may be present in the postoperative period
(2) treat opioid-induced depression of ventilation in the neonate due to maternal
administration of an opioid
(3) facilitate treatment of deliberate opioid
overdose
(4) detect suspected physical dependence.
TRUE or FALSE
Antagonism of opioid-induced depression of ventilation is accompanied by an inevitable reversal of analgesia
TRUE
TRUE or FALSE
Naloxone can easily cross the placenta
TRUE
TRUE or FALSE
Epidural analgesia is 5-10 times more effective than subarachnoid for visceral pain.
TRUE
When given epidurally, the CSF concentration of fentanyl peaks at:
A. 1-4 hours
B. 20 minutes
C. 10 minutes
D. 5 minutes
20 minutes
- Epidural morphine - CSF concetration peak in 20 minutes
Intrathecal morphine plus epinephrine compared to morphine ONLY will:
A. Enhance the analgesia effect
B. No change in analgesia effect
A. Enhance the analgesia effect
TRUE or FALSE
Highly lipid soluble opioid have more rostral spread than less lipid soluble opioid.
FALSE
Highly lipid soluble = less rostral spread
Less lipid soluble = more rostral spread
Urinary retention from neuraxial opioid is primarily attributed to:
A. Inhibition of sacral parasympathetic nervous system outflow
B. The immediate rostral spread of highly lipid soluble opioid
C. Receptors in the PAG sends feedback mechanism to the sacral plexus
Urinary retention is most likely due to interaction of the opioid with opioid receptors located in the sacral spinal cord.
This interaction promotes inhibition of sacral parasympathetic nervous system outflow, which causes detrusor muscle relaxation and an increase in maximum bladder capacity, leading to urinary retention.
- epidural morphine causes marked
detrusor muscle relaxation within 15 minutes of injection that persists for
up to 16 hours
Stoelting Pharmacology | 6th edit
A 20 year old G1P1 was given intrathecal morphine. Early respiratory depression is unlikely to occur.
Why?
What is considered Early respiratory depression versus late respiratory depression?
- Intrathecal morphine is less like to cause early respiratory depression due to it lipophilicity. Less lipophilic means slow rostral spread thus early respiratory depression is not common.
- Early depression of ventilation occurs within 2 hours of neuraxial injection of the opioid
Delayed depression of ventilation occurs more than 2 hours after neuraxial opioid administration and reflects cephalad migration of the opioid in the CSF and subsequent interaction with opioid receptors located in the ventral medulla
TRUE of Codeine except:
A. Equipotent dose of 120 mg codeine is
equivalent in analgesic effect to 10 mg of morphine
B. Codeine is effective at suppressing cough at oral doses of 15 mg
C. The risk of physical dependence appears to be more than that of morphine
D. Histamine release is possible hence it cannot be given via IV route
C. The risk of physical dependence appears to be more than that of morphine —> FALSE statement! The risk of physical dependence is LESS compared to morphine.
This opioid enhances the function of the spinal descending inhibitory pathways by inhibition of neuronal reuptake of norepinephrine and 5- hydroxytryptamine (serotonin) as well as presynaptic stimulation of 5- hydroxytryptamine release:
A. Tramadol
B. Methadone
C. Meperidine
D. Codeine
A. Tramadol
- Remember TRAMADOL is centrally acting hence the different target sites.
Tramadol is a centrally acting analgesic that has moderate affinity for μ receptors and weak κ- and δ-opioid receptor affinity but is 5 to 10 times less potent than morphine as an analgesic
Which of the following opioid agonist-antagonist displays a significant resistance to the the antagonism of naloxone:
A. Buprenorphine
B. Nalbuphine
C. Pentazocine
D. Butorphanol
A. Buprenorphine
Its pharmacokinetics are unique in that it undergoes extensive first-pass metabolism and thus has little oral bioavailability.
It is estimated that the affinity of
buprenorphine for μ receptors is 50 times greater than that of morphine, and
subsequent slow dissociation from these receptors accounts for its prolonged duration of action and resistance to antagonism with naloxone.
Which opioid is considered to have an intermediate strength:
A. Buprenorphine
B. Codeine
C. Alfentanil
D. Tramadol
A. Buprenorphine
Strong opioids: Fentanyl, sufentanil, and
remifentanil
Intermediate: morphine, methadone,
oxycodone, and buprenorphine
Weak opioids: codeine and tramadol
Methadone-induced constipation could be reversed without loss of analgesic effect with which of the following opioid antagonists?
A. Naloxone
B. Nalmefene
C. Naltrexone
D. Methylnaltrexone
D. Methylnaltrexone
