NU 578 Exam: Verified Answers For All Exam Questions
An infant who receives a drug that does not produce CNS side effects in adults
exhibits drowsiness and sedation. The nurse understands that this is because
of differences in which physiologic system in infants and adults?
a. Blood-brain barrier
b. First-pass effect
c. Gastrointestinal absorption
d. Renal filtration Accurate Answer:- A
The blood-brain barrier is not fully developed at birth, making infants much
more sensitive to CNS drugs than older children and adults. CNS symptoms
may include sedation and drowsiness. The first-pass effect and GI absorption
affect metabolism and absorption of drugs, and renal filtration affects
elimination of drugs, all of which may alter drug levels.DIF: Cognitive Level:
ComprehensionREF: pp. 139TOP: Nursing Process: N/A MSC: NCLEX Client
Needs Category: Physiologic Integrity: Physiologic Adaptation
Which monoamines act as neurotransmitters in the central nervous system?
Select all that apply.
a. Acetylcholine
b. Norepinephrine
c. Serotonin
d. Dopamine
e. Epinephrine
f. Histamine Accurate Answer:- B,C,D,E
Acetylcholine and histamines are not monoamines.DIF: Cognitive Level:
ComprehensionREF: pp. 140TOP: Nursing Process: Assessment MSC: NCLEX
Client Needs Category: Physiologic Integrity: Pharmacologic and Parenteral
Therapies
A patient asks a nurse to explain what drug tolerance means. The nurse
responds by telling the patient that when tolerance occurs, it means the
patient:
a. has developed a psychologic dependence on the drug.
,b. may need increased amounts of the drug over time.
c. will cause an abstinence syndrome if the drug is discontinued abruptly.
d. will have increased sensitivity to drug side effects. Accurate Answer:-
B
When tolerance develops, a dose increase may be needed, because a
decreased response may occur with prolonged use. Psychologic dependence
involves cravings for drug effects and does not define tolerance. Physical
dependence occurs when the drug becomes necessary for the brain to
function "normally," meaning the patient should be weaned from the drug
slowly to prevent an abstinence syndrome. Patients may have a decreased
sensitivity to drug side effects over time as the brain adapts to the
medication.DIF: Cognitive Level: ComprehensionREF: pp. 140TOP: Nursing
Process: N/A MSC: NCLEX Client Needs Category: Physiologic Integrity:
Physiologic Adaptation
A group of nursing students asks a nurse to explain the blood-brain barrier.
The nurse would be correct to say that the blood-brain barrier:
a. prevents some potentially toxic substances from crossing into the central
nervous system.
b. causes infants to be less sensitive to CNS drugs and thus require larger
doses.
c. allows only ionized or protein-bound drugs to cross into the central nervous
system.
d. prevents lipid-soluble drugs from entering the central nervous system.
Accurate Answer:- A
The blood-brain barrier can prevent some drugs and some toxic substances
from entering the CNS. The blood-brain barrier in infants is not fully
developed, so infants are more sensitive to CNS drugs and often require lower
doses. The blood-brain barrier prevents highly ionized and protein- bound
drugs from crossing into the CNS and allows lipidsoluble drugs and those that
can cross via specific transport systems to enter.
A nurse is teaching a group of students about how CNS drugs are developed.
Which statement by a student indicates a need for further teaching?
,a. "Central nervous system drug development relies on observations of their
effects on human behavior."
b. "Studies of new central nervous system drugs in healthy subjects can
produce paradoxical effects."
c. "Our knowledge of the neurochemical and physiologic changes that underlie
mental illness is incomplete."
d. "These drugs are developed based on scientific knowledge of CNS
transmitters and receptors." Accurate Answer:- D
The deficiencies in knowledge about how CNS transmitters and receptors
work make systematic development of CNS drugs difficult. Testing in healthy
subjects often leads either to no effect or to paradoxical effects. Medical
knowledge of the neurochemical and physiologic changes underlying mental
illness is incomplete. The development of CNS drugs depends less on
knowledge of how the CNS functions and how these drugs affect that process
and more on how administering one of these agents leads to changes in
behavior.
A nurse is teaching a group of nursing students how the CNS adapts to
psychotherapeutic medications. Which statement by a nursing student
indicates a need for further teaching?
a. "Adaptation can lead to tolerance of these drugs with prolonged use."
b. "Adaptation helps explain how physical dependence occurs."
c. "Adaptation often must occur before therapeutic effects develop."
d. "Adaptation results in an increased sensitivity to side effects over time."
Accurate Answer:- D
With adaptation of the central nervous system to prolonged exposure to CNS
drugs, many adverse effects diminish and therapeutic effects remain.
Adaptation helps explain how tolerance and physical dependence occur, as the
brain adapts to the presence of the drug. Therapeutic effects can take several
weeks to manifest, because they appear to work by initiating adaptive changes
in the brain.
A psychiatric nurse is teaching a patient about an antidepressant medication.
The nurse tells the patient that therapeutic effects may not occur for several
weeks. The nurse understands that this is likely the result of:
, a. changes in the brain as a result of prolonged drug exposure.
b. direct actions of the drug on specific synaptic functions in the brain.
c. slowed drug absorption across the blood-brain barrier.
d. tolerance to exposure to the drug over time. Accurate Answer:- A
It is thought that beneficial responses to central nervous system (CNS) drugs
are delayed because they result from adaptive changes as the CNS modifies
itself in response to prolonged drug exposure, and that the responses are not
the result of the direct effects of the drugs on synaptic functions. The blood-
brain barrier prevents protein-bound and highly ionized drugs from crossing
into the CNS, but it does not slow the effects of drugs that can cross the
barrier. Tolerance is a decreased response to a drug after prolonged use.
Which are medical applications of central nervous system drugs?
Select all that apply.
a. Analgesia
b. Anesthesia
c. Depression
d. Euphoria
e. Seizure control Accurate Answer:- A , B , E
CNS drugs have medical uses for pain management, anesthesia, and seizure
control. Depression and euphoria are side effects that can contribute to abuse
of these drugs.
A nursing student wants to know how carbidopa can be effective for treating
Parkinson disease if it prevents the conversion of levodopa to dopamine. The
nurse explains that carbidopa:
a. can be taken with high-protein meals.
b. does not cross the blood-brain barrier.
c. has dopamine-like effects of its own.
d. reduces abrupt loss of effect. Accurate Answer:- B
Carbidopa inhibits decarboxylation of levodopa in the intestine and peripheral
tissues, leading to more levodopa in the CNS. Carbidopa cannot cross the
blood-brain barrier, so it does not have this action in the CNS. Carbidopa is not
given with high-protein meals. Carbidopa does not have dopamine-like effects.
Carbidopa does not affect abrupt loss of effect.
An infant who receives a drug that does not produce CNS side effects in adults
exhibits drowsiness and sedation. The nurse understands that this is because
of differences in which physiologic system in infants and adults?
a. Blood-brain barrier
b. First-pass effect
c. Gastrointestinal absorption
d. Renal filtration Accurate Answer:- A
The blood-brain barrier is not fully developed at birth, making infants much
more sensitive to CNS drugs than older children and adults. CNS symptoms
may include sedation and drowsiness. The first-pass effect and GI absorption
affect metabolism and absorption of drugs, and renal filtration affects
elimination of drugs, all of which may alter drug levels.DIF: Cognitive Level:
ComprehensionREF: pp. 139TOP: Nursing Process: N/A MSC: NCLEX Client
Needs Category: Physiologic Integrity: Physiologic Adaptation
Which monoamines act as neurotransmitters in the central nervous system?
Select all that apply.
a. Acetylcholine
b. Norepinephrine
c. Serotonin
d. Dopamine
e. Epinephrine
f. Histamine Accurate Answer:- B,C,D,E
Acetylcholine and histamines are not monoamines.DIF: Cognitive Level:
ComprehensionREF: pp. 140TOP: Nursing Process: Assessment MSC: NCLEX
Client Needs Category: Physiologic Integrity: Pharmacologic and Parenteral
Therapies
A patient asks a nurse to explain what drug tolerance means. The nurse
responds by telling the patient that when tolerance occurs, it means the
patient:
a. has developed a psychologic dependence on the drug.
,b. may need increased amounts of the drug over time.
c. will cause an abstinence syndrome if the drug is discontinued abruptly.
d. will have increased sensitivity to drug side effects. Accurate Answer:-
B
When tolerance develops, a dose increase may be needed, because a
decreased response may occur with prolonged use. Psychologic dependence
involves cravings for drug effects and does not define tolerance. Physical
dependence occurs when the drug becomes necessary for the brain to
function "normally," meaning the patient should be weaned from the drug
slowly to prevent an abstinence syndrome. Patients may have a decreased
sensitivity to drug side effects over time as the brain adapts to the
medication.DIF: Cognitive Level: ComprehensionREF: pp. 140TOP: Nursing
Process: N/A MSC: NCLEX Client Needs Category: Physiologic Integrity:
Physiologic Adaptation
A group of nursing students asks a nurse to explain the blood-brain barrier.
The nurse would be correct to say that the blood-brain barrier:
a. prevents some potentially toxic substances from crossing into the central
nervous system.
b. causes infants to be less sensitive to CNS drugs and thus require larger
doses.
c. allows only ionized or protein-bound drugs to cross into the central nervous
system.
d. prevents lipid-soluble drugs from entering the central nervous system.
Accurate Answer:- A
The blood-brain barrier can prevent some drugs and some toxic substances
from entering the CNS. The blood-brain barrier in infants is not fully
developed, so infants are more sensitive to CNS drugs and often require lower
doses. The blood-brain barrier prevents highly ionized and protein- bound
drugs from crossing into the CNS and allows lipidsoluble drugs and those that
can cross via specific transport systems to enter.
A nurse is teaching a group of students about how CNS drugs are developed.
Which statement by a student indicates a need for further teaching?
,a. "Central nervous system drug development relies on observations of their
effects on human behavior."
b. "Studies of new central nervous system drugs in healthy subjects can
produce paradoxical effects."
c. "Our knowledge of the neurochemical and physiologic changes that underlie
mental illness is incomplete."
d. "These drugs are developed based on scientific knowledge of CNS
transmitters and receptors." Accurate Answer:- D
The deficiencies in knowledge about how CNS transmitters and receptors
work make systematic development of CNS drugs difficult. Testing in healthy
subjects often leads either to no effect or to paradoxical effects. Medical
knowledge of the neurochemical and physiologic changes underlying mental
illness is incomplete. The development of CNS drugs depends less on
knowledge of how the CNS functions and how these drugs affect that process
and more on how administering one of these agents leads to changes in
behavior.
A nurse is teaching a group of nursing students how the CNS adapts to
psychotherapeutic medications. Which statement by a nursing student
indicates a need for further teaching?
a. "Adaptation can lead to tolerance of these drugs with prolonged use."
b. "Adaptation helps explain how physical dependence occurs."
c. "Adaptation often must occur before therapeutic effects develop."
d. "Adaptation results in an increased sensitivity to side effects over time."
Accurate Answer:- D
With adaptation of the central nervous system to prolonged exposure to CNS
drugs, many adverse effects diminish and therapeutic effects remain.
Adaptation helps explain how tolerance and physical dependence occur, as the
brain adapts to the presence of the drug. Therapeutic effects can take several
weeks to manifest, because they appear to work by initiating adaptive changes
in the brain.
A psychiatric nurse is teaching a patient about an antidepressant medication.
The nurse tells the patient that therapeutic effects may not occur for several
weeks. The nurse understands that this is likely the result of:
, a. changes in the brain as a result of prolonged drug exposure.
b. direct actions of the drug on specific synaptic functions in the brain.
c. slowed drug absorption across the blood-brain barrier.
d. tolerance to exposure to the drug over time. Accurate Answer:- A
It is thought that beneficial responses to central nervous system (CNS) drugs
are delayed because they result from adaptive changes as the CNS modifies
itself in response to prolonged drug exposure, and that the responses are not
the result of the direct effects of the drugs on synaptic functions. The blood-
brain barrier prevents protein-bound and highly ionized drugs from crossing
into the CNS, but it does not slow the effects of drugs that can cross the
barrier. Tolerance is a decreased response to a drug after prolonged use.
Which are medical applications of central nervous system drugs?
Select all that apply.
a. Analgesia
b. Anesthesia
c. Depression
d. Euphoria
e. Seizure control Accurate Answer:- A , B , E
CNS drugs have medical uses for pain management, anesthesia, and seizure
control. Depression and euphoria are side effects that can contribute to abuse
of these drugs.
A nursing student wants to know how carbidopa can be effective for treating
Parkinson disease if it prevents the conversion of levodopa to dopamine. The
nurse explains that carbidopa:
a. can be taken with high-protein meals.
b. does not cross the blood-brain barrier.
c. has dopamine-like effects of its own.
d. reduces abrupt loss of effect. Accurate Answer:- B
Carbidopa inhibits decarboxylation of levodopa in the intestine and peripheral
tissues, leading to more levodopa in the CNS. Carbidopa cannot cross the
blood-brain barrier, so it does not have this action in the CNS. Carbidopa is not
given with high-protein meals. Carbidopa does not have dopamine-like effects.
Carbidopa does not affect abrupt loss of effect.