NSG 552 Exam 1 V1 | NSG 552
Psychopharmacology | Actual Q&A with Rationale
(NSG 552 Exam 1) | Wilkes
1. A patient is prescribed a new medication that is a potent inhibitor of the CYP 2D6 enzyme.
Which of the following consequences is most likely to occur if the patient is also taking a
substrate of this enzyme?
A. Decreased plasma levels of the substrate drug due to increased metabolism.
B. Induction of the enzyme system, requiring a higher dose of the substrate.
C. Increased plasma levels of the substrate drug, leading to potential toxicity.
D. No change in plasma levels as 2D6 is not involved in drug metabolism.
Correct Answer: C
Explanation: Inhibition of a cytochrome P450 enzyme like 2D6 prevents the breakdown of
medications that utilize that pathway. This leads to an accumulation of the substrate drug
in the systemic circulation. Consequently, the patient is at a significantly higher risk for
drug-induced toxicity and adverse effects.
2. Which dopamine pathway is primarily responsible for the development of extrapyramidal
symptoms (EPS) when D2 receptors are blocked by first-generation antipsychotics?
A. Mesolimbic pathway
B. Mesocortical pathway
,C. Nigrostriatal pathway
D. Tuberoinfundibular pathway
Correct Answer: C
Explanation: The nigrostriatal pathway projects from the substantia nigra to the striatum
and controls motor function. Blockade of D2 receptors in this specific area leads to
movement disorders known as extrapyramidal symptoms. This distinguishes it from the
mesolimbic pathway, which is associated with the therapeutic reduction of positive
symptoms.
3. A 24-year-old patient starts Fluoxetine for depression. Why is it important to wait at least 5
weeks before switching from Fluoxetine to a Monoamine Oxidase Inhibitor (MAOI)?
A. To prevent the risk of hypertensive crisis caused by tyramine.
B. Due to the exceptionally long half-life of Fluoxetine and its active metabolite.
C. To allow the downregulation of serotonin receptors to reverse.
D. Fluoxetine causes permanent enzyme inhibition that takes weeks to regenerate.
Correct Answer: B
Explanation: Fluoxetine has a very long half-life, especially its active metabolite
norfluoxetine, which can stay in the system for weeks. Switching to an MAOI too quickly
can lead to Serotonin Syndrome because both drugs increase serotonin levels through
different mechanisms. A 5-week washout period is strictly required to ensure the drug is
completely cleared from the body.
, 4. Which of the following describes the ‘First-Pass Effect’ in pharmacokinetics?
A. The initial distribution of a drug to highly vascularized organs like the brain.
B. The rapid metabolism of an orally administered drug in the liver before reaching
systemic circulation.
C. The process of a drug binding to plasma proteins during the first hour of administration.
D. The excretion of a drug through the kidneys immediately after the first dose.
Correct Answer: B
Explanation: The first-pass effect occurs when a medication is absorbed from the
gastrointestinal tract and enters the portal vein to the liver. The liver metabolizes a
significant portion of the drug before it ever reaches the rest of the body. This phenomenon
explains why oral doses are often much higher than intravenous doses for the same
medication.
5. A patient taking Clozapine must have regular blood work to monitor for which life-
threatening adverse effect?
A. Hepatotoxicity
B. Stevens-Johnson Syndrome
C. Nephrogenic diabetes insipidus
D. Agranulocytosis
Correct Answer: D
Psychopharmacology | Actual Q&A with Rationale
(NSG 552 Exam 1) | Wilkes
1. A patient is prescribed a new medication that is a potent inhibitor of the CYP 2D6 enzyme.
Which of the following consequences is most likely to occur if the patient is also taking a
substrate of this enzyme?
A. Decreased plasma levels of the substrate drug due to increased metabolism.
B. Induction of the enzyme system, requiring a higher dose of the substrate.
C. Increased plasma levels of the substrate drug, leading to potential toxicity.
D. No change in plasma levels as 2D6 is not involved in drug metabolism.
Correct Answer: C
Explanation: Inhibition of a cytochrome P450 enzyme like 2D6 prevents the breakdown of
medications that utilize that pathway. This leads to an accumulation of the substrate drug
in the systemic circulation. Consequently, the patient is at a significantly higher risk for
drug-induced toxicity and adverse effects.
2. Which dopamine pathway is primarily responsible for the development of extrapyramidal
symptoms (EPS) when D2 receptors are blocked by first-generation antipsychotics?
A. Mesolimbic pathway
B. Mesocortical pathway
,C. Nigrostriatal pathway
D. Tuberoinfundibular pathway
Correct Answer: C
Explanation: The nigrostriatal pathway projects from the substantia nigra to the striatum
and controls motor function. Blockade of D2 receptors in this specific area leads to
movement disorders known as extrapyramidal symptoms. This distinguishes it from the
mesolimbic pathway, which is associated with the therapeutic reduction of positive
symptoms.
3. A 24-year-old patient starts Fluoxetine for depression. Why is it important to wait at least 5
weeks before switching from Fluoxetine to a Monoamine Oxidase Inhibitor (MAOI)?
A. To prevent the risk of hypertensive crisis caused by tyramine.
B. Due to the exceptionally long half-life of Fluoxetine and its active metabolite.
C. To allow the downregulation of serotonin receptors to reverse.
D. Fluoxetine causes permanent enzyme inhibition that takes weeks to regenerate.
Correct Answer: B
Explanation: Fluoxetine has a very long half-life, especially its active metabolite
norfluoxetine, which can stay in the system for weeks. Switching to an MAOI too quickly
can lead to Serotonin Syndrome because both drugs increase serotonin levels through
different mechanisms. A 5-week washout period is strictly required to ensure the drug is
completely cleared from the body.
, 4. Which of the following describes the ‘First-Pass Effect’ in pharmacokinetics?
A. The initial distribution of a drug to highly vascularized organs like the brain.
B. The rapid metabolism of an orally administered drug in the liver before reaching
systemic circulation.
C. The process of a drug binding to plasma proteins during the first hour of administration.
D. The excretion of a drug through the kidneys immediately after the first dose.
Correct Answer: B
Explanation: The first-pass effect occurs when a medication is absorbed from the
gastrointestinal tract and enters the portal vein to the liver. The liver metabolizes a
significant portion of the drug before it ever reaches the rest of the body. This phenomenon
explains why oral doses are often much higher than intravenous doses for the same
medication.
5. A patient taking Clozapine must have regular blood work to monitor for which life-
threatening adverse effect?
A. Hepatotoxicity
B. Stevens-Johnson Syndrome
C. Nephrogenic diabetes insipidus
D. Agranulocytosis
Correct Answer: D
