Chapter 4. Pharmacology Flashcards
1
Q
- Which of the following is true regarding seizures
as one of the multiple side effects from the use
of opioids?
(A) Morphine and related opioids can cause
seizure activity when moderate doses
are given
(B) Seizure activity is more likely with
meperidine, especially in the elderly
and with renal dysfunction
(C) Seizure activity is mediated through
stimulation of N-methyl-D-aspartate
(NMDA) receptors
(D) Naloxone is very effective in treating
seizures produced by morphine and
related drugs including meperidine
(E) Seizure activity is most likely related
with the fact that opioids stimulate the
production of γ-aminobutyric acid
(GABA)
A
- (B) Extremely high doses of morphine and
related opioids can produce seizures, presumably
by inhibiting the release of GABA
(at synaptic level).
Normeperidine a metabolite of meperidine
is prone to produce seizures and tends to
accumulate in patients with renal dysfunction
and in the elderly.
Naloxone may not effectively treat seizures
produced by meperidine.
2
Q
- Which of the following is true regarding respiratory
depression related to the use of opioids?
(A) Opioid agonists, partial agonists, and
agonist/antagonists produce the same
degree of respiratory depression
(B) Opioids produce a leftward shift of the
CO2 response curve
(C) Depression of respiration is produced
by a decrease in respiratory rate, with a
constant minute volume
(D) Naloxone partially reverses the opioidinduced
respiratory depression
(E) The apneic threshold is decreased
A
- (E) Opioids produce a dose-dependant respiratory
depression by acting directly on the respiratory
centers on the brainstem. Partial agonist
and agonist-antagonist opioids are less likely to
cause severe respiratory depression, as are the
selective K-agonist.
Therapeutic doses of morphine decrease
minute ventilation by decreasing respiratory
rate (as oppose to tidal volume).
Opioids depress the ventilatory response
to carbon dioxide; the carbon dioxide–response
curve shows a decrease slope and rightward
shift.
The apneic threshold is decreased and also
the increase in ventilatory response to hypoxemia
is blunted by opioids.
Naloxone can effectively and fully reverse
the respiratory depression from opioids.
3
Q
- The use of which of the following opioids would
produce the greatest incidence of delayed respiratory
depression?
(A) 25 μg intravenous (IV) fentanyl (bolus)
(B) 4 mg IV morphine (bolus)
(C) 5 μg IV sufentanil (bolus)
(D) 8 mg epidural, preservative free
morphine
(E) 0.05 mg intrathecal, preservative free
morphine
A
- (D) Delayed respiratory depression is likely to
occur with larger dose of epidural opioids, particularly
morphine which is hydrophilic and
therefore subject to spread in the cerebrospinal
fluid (CSF), reaching the respiratory center in
the brainstem.
Intrathecal doses of morphine produce only
a uniphasic pattern of respiratory depression.
4
Q
144. Opioids in general reduce the sympathetic output and produce a dose-dependant bradycardia, EXCEPT (A) morphine (B) fentanyl (C) meperidine (D) sufentanil (E) alfentanil
A
- (C) High doses of any opioid reduce sympathetic
output allowing the parasympathetic
output to predominate. The heart rate decreases
by stimulation of the vagal center, especially
with high-doses.
Meperidine because of its similarity to
atropine may elevate the heart rate after IV
administration
5
Q
- What is the main mechanism by which opioids
produce analgesia?
(A) Coupling of opioid receptors to sodium
and potassium ion channels, therefore
inhibiting neurotransmitter release
(presynaptic) and inhibiting neuronal
firing (postsynaptically)
(B) Coupling of opioid receptor to potassium
and calcium channels, inhibiting
neurotransmitter release (presynaptic),
and inhibiting neuronal firing (postsynaptically)
(C) Coupling of opioid receptors to sodium
and calcium channels, inhibiting
neurotransmitter release (presynaptic),
and inhibiting neuronal firing
(postsynaptically)
(D) Coupling of opioid receptors to potassium
and calcium channels, inhibiting
neuronal firing (presynaptically), and
inhibiting neurotransmitter release
(postsynaptically)
(E) All the options are true
A
- (B) Opioid receptors are coupled to G proteins,
able to affect most of the time, protein phosphorylation
via a second messenger, thereby
altering the conductance of potassium and calcium
ion channels. This is believed to be the
main mechanisms by which endogenous and
exogenous opioids produce analgesia.
The opening of potassium channels—the most
well documented—will inhibit the release of neurotransmitters,
including substance P and glutamate
if the receptors are presynaptic. And will
inhibit neuronal firing by hyperpolarization of the
cell if the receptors are postsynaptic on the neurons.
6
Q
- Main mechanics of spinal opioid analgesia is via
(A) activation of presynaptic opioid receptors
(B) activation of postsynaptic opioid
receptors
(C) activation of opioid receptors on the
midbrain
(D) activation of opioid receptors on the RVM
(E) all of the above
A
- (A) The different type of opioid receptors contribute
in different proportions to the total
opioid receptors in the spinal cord. μ-Receptors
constitute 70%, δ-receptors 24% and κ-receptors
6%. The main mechanism of spinal opioid analgesia
is through presynaptic activation of opioid
receptors.
Opioid receptors are synthesized in small
diameter DRG cell bodies and transported centrally
and peripherally. They are mainly (70%)
located presynaptically on small diameter nociceptive
primary afferents (C and A-δ fibers).
7
Q
147. Opioids act on what type of receptors targets? (A) μ-, δ-, κ-, And ORL receptors (B) Voltage-dependent sodium channels (C) α2B-Adrenoreceptors (D) NMDA receptors (E) All of the above
A
- (E) Opioids produce analgesia primarily through
interaction with μ-receptors. The activation of κ-
and δ-receptors also causes analgesia.The ORL receptor is a member of the opioid
receptors, although ligands do not have the same
high affinity for this type of receptors, but effects
of high-affinity ligands, such as antinociception,
proprioception/hyperalgesia, allodynia and no
effect have been reported.
Analysis has shown that some opioid
actions are not mediated by opioid receptors,
morphine can inhibit voltage-dependant sodium
(Na) current, meperidine can block voltage-
dependant sodium (Na) channels.
Meperidine also has agonist activity at the
α2B-adrenoreceptor subtype.
Methadone, meperidine, and tramadol
inhibit serotonin and norepinephrin reuptake.
High concentrations of opioids, including
morphine, fentanyl, codeine, and naloxone
directly inhibit NMDA receptor.
8
Q
148. Which of the following statements is true regarding the use of oxycodone? (A) Analgesic efficacy is not comparable with that of morphine (B) Typically has been used in combination with nonopioids (C) Not available as a long-acting preparation (D) Lower bioavailability than that of morphine (E) Consistently shows a higher induced rate of hallucinations and itching when compared with morphine
A
- (B) Oxycodone a semisynthetic derivative of
thebaine and has analgesic efficacy comparable
with that of morphine, with a median oxycodone
to morphine dose ratio of 1 to 15.
Oxycodone has been typically used in
combination with nonopioids (acetaminophen,
aspirin) and a long-acting preparation is available,
which has popularized its use in cancer
patients.
It has a higher bioavailability than that of
morphine (approximately 60%).
There are not consistent observations on
reduced rate of hallucinations and itching when
compared with morphine.
9
Q
- One important characteristic of methadone that
has to be considered when prescribing it on an
outpatient basis:
(A) Usually there is a low chance for interactions
on patients taking multiple
medications
(B) Withdrawal symptoms are as severe as
with morphine
(C) Rarely used in opioid addiction
(D) Sedation and respiratory depression can
outlast the analgesic action
(E) Allows rapid titration
A
- (D) Methadone unlike morphine is metabolized
through N-demethylation by the liver
cytochrome P-450 enzyme, which activity can
vary widely in different people.
Methadone should be administered with
caution in patients receiving multiple medications,
specially antivirals and antibiotics.
Methadone’s withdrawal symptoms tend to
be less severe than morphine’s, this and its long
duration of action, good oral bioavailability, and
high potency made it the maintenance drug or
detoxification treatment of opioid addiction.
Methadone has biphasic elimination. Along
β-elimination phase (ranges from 30 to 60 hours)
producing sedation and respiratory depression
can outlast the analgesic action which equates
the α-elimination phase (6-8 hours).This biphasic
pattern explains why methadone is required
once a day for opioid maintenance therapy and
every 4 to 8 hours for analgesia.
Rapid titration is not possible, making this
drug more useful for stable type of pain.
10
Q
150. What property of methadone makes it a good option for opioid rotation, when tolerance develops? (A) Serotonin agonist (B) α2B-Adrenoreceptor agonist (C) μ-Agonist (D) NMDA agonist (E) NMDA antagonist
A
- (E) When tolerance to opioids, usually after
use over long periods of time, opioid rotation,
resting period off opioids, and addition of an
NMDA antagonist are a number of strategies
available.
Opioid rotation, switching from one opioid
to another may be helpful because of partial
cross tolerance between opioids. Because
methadone has NMDA receptor antagonist
properties, makes it a good choice.
Methadone is: μ- and δ-antagonist, NMDA
inhibitor, inhibitor of serotonin and norepinephrine
reuptake.
11
Q
151. Which one of the following is the only opioid with prolonged activity not achieved by controlled-released formulation? (A) Oxycodone (B) Fentanyl (C) Morphine (D) Codeine (E) Methadone
A
- (E) Methadone is the only opioid with prolonged
activity not achieved by controlledrelease
formulation.
Oxycodone can be formulated as controlledrelease.
Codeine half-life is 2 to 4 hours.
12
Q
152. Which of the following opioids is used in the office-based treatment of addiction? (A) Naloxone (B) Morphine (C) Tramadol (D) Buprenorphine (E) Meperidine
A
- (D) Buprenorphine is a semisynthetic opioid
with partial activity at the μ-receptor and very
little activity at the κ- and δ-receptors.
It has high affinity but low intrinsic activity
at the μ-receptor and has a pharmacologic
ceiling owing to its partial agonist activity.
It is available in the United States to be
used in the office-based treatment of addiction.
It can be given for withdrawal of heroin or
methadone, or used as a maintenance of addicts.
13
Q
153. Pharmacologic properties of fentanyl that make it an ideal drug for transdermal and transmucosal administration is (A) high lipid solubility, high molecular weight, and high potency (B) low lipid solubility, high molecular weight, and high potency (C) low lipid solubility, low molecular weight, and low potency (D) high lipid solubility, low molecular weight, and high potency (E) high lipid solubility, low molecular weight, and low potency
A
- (D) Fentanyl is a potent mu agonist, with high
lipid solubility, low molecular weight and high
potency, making it an ideal drug for transdermal
and transmucosal administration.
92% of fentanyl delivered transdermally
reaches the circulation as unchanged fentanyl.
Transmucosal route at the buccal and sublingual
mucosa skips the first pass effect and
overall bioavailability is 50%.
14
Q
- Opioids can have drug interactions with
(A) tricyclic antidepressants (TCAs)
(B) selective serotonin reuptake inhibitor
(SSRIs)
(C) monoamine oxidase inhibitors (MAOIs)
(D) metoprolol
(E) all of the above
A
- (E) Opioids can have interactions with multiple
medications, including all the medications
mentioned above. One of the most remarkable interactions occurs if meperidine and MAOIs are combined,
severe respiratory depression or excitation,
arrhythmias, delusions, hyperpyrexia,
seizures and coma can be seen
15
Q
155. Which of the following is a long and cumbersome research tool for substance abuse and is very good but not very practical in the setting of a busy pain clinic? (A) Screening Tool for Addiction Risk (STAR) (B) Severity of Opiate Dependence Questionnaire (SODQ) (C) Screening Instrument for Substance Abuse Potential (SISAP) (D) Addiction Severity Index (ASI) (E) Prescription Drug Use Questionnaire (PDUQ)
A
- (D) The Addiction Severity Index (ASI) is especially
effective for evaluating the need for
substance-abuse treatment. It is a 200-item,
hour-long assessment of seven potential problem
areas designed to be administered by a
trained interviewer.
16
Q
- An opioid specific five-question self-administered
tool which can be completed in less than 5 minutes
to help predict patients at high-risk for
exhibiting aberrant opioid-related behavior is
(A) Prescription Drug Use Questionnaire
(PDUQ)
(B) Opioid Risk Tool (ORT)
(C) Screener and Opioid Assessment for
Patients with Pain (SOAPP)
(D) Screening Instrument for Substance
Abuse Potential (SISAP)
(E) Severity of Opiate Dependence
Questionnaire (SODQ)
A
- (B) The Opioid Risk Tool (ORT) is a fivequestion
self-administered assessment that can
be completed in less than 5 minutes and used
on a patient’s initial visit. Personal and family
history of substance abuse; age; history of
preadolescent sexual abuse; and the presence of
depression, attention-deficit disorder (ADD),
obsessive-compulsive disorder (OCD), bipolar
disorder, and schizophrenia are assessed. The
ORT accurately predicted which patients were
at the highest and the lowest risk for exhibiting
aberrant, drug-related behaviors associated
with abuse or addiction.
17
Q
157. The opioid which is largely metabolized by CYP3A4 is (A) morphine (B) fentanyl (C) methadone (D) hydromorphone (E) oxymorphone
A
- (B)
18
Q
- Which of the following is correct regarding
patients who are prescribed and taking
hydrocodone and found to have different opioid
in their urine drug-testing results?
(A) Norfentanyl, which is expected
(B) Hydrocodeine, which is expected as a
normal metabolite
(C) Hydromorphone, which is expected as a
normal metabolite
(D) Hydromorphone, which is unexpected
and patient is probably taking another
opioid
(E) Hydrocodeine, which is unexpected and
patient is probably taking another
opioid
A
- (C)
19
Q
- An opioid-specific instrument which may be
useful in predicting opioid misuse and is available
as a 5-, 14-, or 24-item questionnaire as well
as a revised version designed to be less susceptible
to overt deception than the original version is
(A) Prescription Drug Use Questionnaire
(PDUQ)
(B) Opioid Risk Tool (ORT)
(C) Screener and Opioid Assessment for
Patients with Pain (SOAPP)
(D) Screening Instrument for Substance
Abuse Potential (SISAP)
(E) Severity of Opiate Dependence
Questionnaire (SODQ)
A
- (C) Screener and Opioid Assessment for
Patients with Pain (SOAPP) is a survey tool
used to predict opioid abuse and is available as
a 5-, 14-, 24-item questionnaire. Although the
five-item questionnaire [SOAPP V LO-SF (5Q)]
is less sensitive and specific than the longer
version, it may suffice for use in primary care
settings. The SOAPP-SF is scored by adding
up the ratings of each of the five questions. The
SQ SOAPP uses a cutoff score of 4 or above
(of a possible 20) with a score of more than 4,
indicating that the subject may have a potentially
increased risk of opioid abuse.
20
Q
160. Aclassic example of an opioid partial agonist is (A) naltrexone (B) butorphanol (C) nalbuphine (D) buprenorphine (E) pentazocine
A
- (D)
21
Q
- A popular mnemonic for following relevant
domains of outcome in pain management for
patients on long-term opioid therapy is the socalled
4 A’s which include all the following,
EXCEPT
(A) analgesia
(B) activities of daily living
(C) adverse events
(D) affect
(E) aberrant drug-taking behaviors
A
- (D)
22
Q
162. A popular pain assessment scale which is utilized by preverbal toddler and nonverbal children through age 7 years who may be treated with opioids is (A) CRIES (B) APPT (C) FACES (D) FLAC C (E) N-PASS
A
- (D)
23
Q
163. The opioid which has some component of metabolism by CYP1A2 is (A) morphine (B) fentanyl (C) methadone (D) hydromorphone (E) oxymorphone
A
- (C)
24
Q
164. The opioid which is a metabolite of oxycodone via 3-0-demethylation is (A) hydrocodone (B) morphine (C) codiene (D) hydromorphone (E) oxymorphone
A
- (E)
25
Q
- Which of the following two opioids are inherently,
pharmacologically, and relatively longacting?
(A) Morphine and oxycodone
(B) Morphine and oxymorphone
(C) Oxycodone and fentanyl
(D) Methadone and levorphanol
(E) Methadone and oxymorphone
A
- (D)
26
Q
- Oral transmucosal fentanyl citrate (OTFC) is
applied against the buccal mucosa. The percentage
of the total dose which is absorbed
from the gastrointestinal (GI) tract but escapes
hepatic and intestinal first-pass elimination is
(A) 25%
(B) 33%
(C) 50%
(D) 65%
(E) 75%
A
- (A)
27
Q
167. OTFC is applied against the buccal mucosa. The total apparent bioavailability is (A) 25% (B) 33% (C) 50% (D) 65% (E) 75%
A
- (C)
28
Q
168. The fentanyl buccal tablet (FBT) utilizes an effervescent drug delivery system and achieves an absolute bioavailability of (A) 25% (B) 33% (C) 50% (D) 65% (E) 75%
A
- (D)
29
Q
- After intramuscular administration of fentanyl
citrate, the time to onset of analgesia is roughly
(A) 1 to 3 minutes
(B) 7 to 15 minutes
(C) 15 to 30 minutes
(D) 20 to 40 minutes
(E) 30 to 50 minutes
A
- (B)
30
Q
170. The oral bioavailability of morphine is roughly (A) 10% to 20% (B) 25% to 35% (C) 35% to 45% (D) 40% to 55% (E) 50% to 60%
A
- (B)
31
Q
171. In humans, methadone acts as (A) an agonist-antagonist (B) a pure μ-agonist (C) a μ-agonist but also with significant actions at the δ-opioid receptor (D) a μ-agonist but also with significant actions at the κ-receptor (E) a μ-, δ-, and κ-agonist
A
- (B)
32
Q
172. Atool which documents a quantitative assessment of various opioid-adverse effects is the (A) Pain Assessment and Documentation Tool (PADT) (B) Translational Analgesic Score (TAS) (C) SAFE score (D) Numerical Opioid Side Effect (NOSE) (E) Severity of Opioid Dependence Questionnaire (SODQ)
A
- (D)
33
Q
173. Which of the following is the best opioid to administer for analgesia in a patient with chronic kidney disease stage V? (A) Codeine (B) Meperidine (C) Morphine (D) Fentanyl (E) Propoxyphene
A
- (D)
34
Q
- Which of the following is the most prescribed
opioid in the United States, which also undergoes
O-demethylation to dihydromorphine and
its major metabolites excreted into the urine are
dihydrocodeine and nordihydrocodeine?
(A) Codeine
(B) Dihydrocodeine
(C) Hydrocodone
(D) Hydromorphone
(E) Morphine
A
- (C)
35
Q
- Which of the following is essentially responsible
for opioid-induced respiratory depression?
(A) μ-Receptor
(B) δ-Receptor
(C) κ-Receptor
(D) σ-Receptor
(E) ORL 1 receptor
A
- (A)
36
Q
- Propoxyphene napsylate has a higher maximum
daily dose than propoxyphene hydrochloride
because
(A) propoxyphene napsylate is less potent
than propoxyphene hydrochloride
(B) propoxyphene napsylate is less toxic
than propoxyphene hydrochloride
(C) propoxyphene napsylate is cleared
faster than propoxyphene hydrochloride
(D) the napsylate salt tends to be absorbed
more slowly than the hydrochloride
(E) the napsylate salt makes propoxyphene
less active
A
- (D)
37
Q
177. When considering opioid rotation to methadone, which of the following is the most appropriate next step? (A) Maintain the equianalgesic dose (B) Reduce the dose by 10% to 25% (C) Reduce the dose by 25% to 50% (D) Reduce the dose by 50% to 75% (E) Reduce the dose by 75% to 90%
A
- (E)
38
Q
178. When considering opioid rotation to fentanyl, which of the following is the most appropriate step? (A) Maintain the equianalgesic dose (B) Reduce the dose by 10% to 25% (C) Reduce the dose by 25% to 50% (D) Reduce the dose by 50% to 75% (E) Reduce the dose by 75% to 90%
A
- (A)
39
Q
179. The equianalgesic conversion ratio of oral oxymorphone to intravenous morphine is (A) 1 to 1 (B) 1 to 2 (C) 1 to 3 (D) 1 to 4 (E) 1 to 5
A
- (A)
40
Q
- By approximately what percentage is codeine
ineffective as an analgesic in the Caucasian
population owing to genetic polymorphisms
in CYP2D6 (the enzyme necessary to Omethylate
codeine to morphine)?
(A) 2%
(B) 5%
(C) 10%
(D) 25%
(E) 33%
A
- (C)
41
Q
- Which of the following is the correct statement
regarding the pharmacologic properties of
NSAIDs?
(A) They readily cross the blood–brain
barrier
(B) Their chemical structure consists of aromatic
rings connected to basic functional
groups
(C) They act mainly in the periphery
(D) They have a high renal clearance
(E) They are not metabolized by the liver
A
- (C) The NSAIDs are weak organic acids, consisting
in one or two aromatic rings connected to
an acidic functional group. They do not cross
the blood–brain barrier, are 95% to 99% bound
to albumin, are extensively metabolized by the
liver and have low renal clearance (
42
Q
- What are the advantages of COX-2 inhibitors
versus NSAIDs?
(A) Protective renal effects
(B) Less GI side effects
(C) Protective cardiovascular effects
(D) Inhibits production of thromboxane A2
(E) Increases production of lipooxygenase
A
- (B) Coxibs do not have any advantages in
terms of renal effects.
COX-2 inhibitors are associated with less
GI toxicity than standard NSAIDs but they are
more expensive.
There is a possible increased risk of myocardial
infarction (MI) and thrombotic stroke events
associated with the continuosly long-term use of
coxibs. Those concerns led to rofecoxib and
valdecoxib being withdrawn from the market in
the year 2004 and 2005, respectively.
Regular NSAIDs inhibit the synthesis of
TXA2 by inhibiting COX-1, which is spared
with the use of COX-2 inhibitors.
43
Q
183. Which of the following best fits the pharmacologic mechanisms of action of “traditional” NSAIDs? (A) Inhibition of phospholipase A2 (B) Inhibition of COX-2 (C) Inhibition of lipoxygenase (D) Inhibition of arachidonic acid (E) Inhibition of prostaglandin G/H synthase enzymes
A
- (E) NSAIDs inhibits the prostaglandin G/H
synthase enzymes, colloquially known as the
COX, therefore inhibiting the synthesis of
prostaglandin E, prostacyclin, and thromboxane.
NSAIDs inhibit the production of not only
COX-2 but also COX-1.
Steroids inhibit phospholipase A2.
44
Q
- The main role of prostaglandins in pain is
(A) as important primary pain mediators
(B) sensitization of central nociceptors
(C) sensitization of peripheral nociceptors
(D) facilitation of the production of pain
mediators (ie, bradykinin, somatostatin,
histamine)
(E) stimulation of κ-receptors on the spinal
cord
A
- (C) Prostaglandins are not important primary
pain mediators, they do cause hyperalgesia by
sensitizing peripheral nociceptors (to mechanical
an chemical stimulation) to the effects of pain
mediators, such as bradykinin, somatostatin,
and histamine, producing hyperalgesia. They
do so by lowering the threshold of the polymodal
nociceptors of C fibers.
NSAIDs act mainly in the periphery, but
they may have a central effect. COX-2 induction
within the spinal cord may play an important
role in central sensitization. The acute
antihyperalgesic action of NSAIDs has been
shown to be mediated by the inhibition of constitutive
spinal COX-2, which has been found
to be upregulated in response to inflammation
and other stressors.