NR 546 Week 4 Midterm Exam Advanced
Psychopharmacology Mental Health Official
Practice Exam Actual Exam 2026/2027 with
Detailed Rationales | Complete Exam-Style
Questions | Pass Guaranteed – A+ Graded
══════════════════════════════════════
SECTION 1: NEUROBIOLOGY & PHARMACODYNAMICS Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 34-year-old woman with treatment-resistant depression is being evaluated for
augmentation with brexpiprazole. The psychiatric-mental health NP explains to the patient
that brexpiprazole's therapeutic effect in depression is primarily mediated through which
receptor mechanism?
A. Full antagonism of D2 receptors and inverse agonism at 5-HT2A receptors
B. Partial agonism at D2 and 5-HT1A receptors with antagonism at 5-HT2A receptors ✓
CORRECT
C. Full agonism at D2 receptors and antagonism at H1 receptors
D. Partial agonism at M1 muscarinic receptors and antagonism at alpha-1 adrenergic
receptors
Correct Answer: B
Rationale: Brexpiprazole is a serotonin-dopamine activity modulator (SDAM) that acts as a
partial agonist at D2 and 5-HT1A receptors while antagonizing 5-HT2A receptors; this unique
profile provides antidepressant augmentation with a lower risk of extrapyramidal symptoms
compared to full D2 antagonists. Option A describes the mechanism of aripiprazole, which
shares partial agonist properties but brexpiprazole has a higher affinity for 5-HT1A and lower
intrinsic activity at D2, making it distinct. On the NR 546 exam, always distinguish partial
agonist mechanisms from full antagonism when evaluating second-generation
antipsychotics used as adjunctive therapy.
Question 2 of 50
A 28-year-old man with bipolar disorder is prescribed lithium carbonate 900 mg daily. At his
3-month follow-up, his serum lithium level is 0.4 mEq/L, and he reports continued mood
,cycling. The NP recalls that lithium's mood-stabilizing effect is most closely linked to its
action on which intracellular signaling pathway?
A. Direct inhibition of GABA-A receptor chloride channels
B. Inhibition of inositol monophosphatase and glycogen synthase kinase-3 (GSK-3) ✓
CORRECT
C. Blockade of NMDA receptor calcium influx
D. Activation of adenylyl cyclase and increased cAMP production
Correct Answer: B
Rationale: Lithium exerts its mood-stabilizing effects primarily through inhibition of inositol
monophosphatase, which depletes inositol and dampens phosphoinositide signaling, and
through inhibition of glycogen synthase kinase-3 (GSK-3), which regulates neuroplasticity and
circadian rhythms. Option D is incorrect because lithium actually inhibits adenylyl cyclase
rather than activating it, and this mechanism is more relevant to its adverse effects on
thyroid function than its primary mood-stabilizing action. Remember that lithium has a narrow
therapeutic index (0.6–1.2 mEq/L for acute mania), and levels below 0.6 mEq/L are generally
subtherapeutic for mood stabilization.
Question 3 of 50
A 42-year-old woman with panic disorder is started on sertraline 25 mg daily. After 2 weeks,
she reports increased anxiety and jitteriness. The NP explains that this early activation is
most likely related to sertraline's initial effects on which neurotransmitter system before
downstream adaptive changes occur?
A. Rapid downregulation of beta-adrenergic receptors in the locus coeruleus
B. Acute increase in synaptic serotonin leading to stimulation of 5-HT2A and 5-HT3 receptors
✓ CORRECT
C. Immediate upregulation of GABA-B receptors in the amygdala
D. Delayed inhibition of norepinephrine reuptake in the prefrontal cortex
Correct Answer: B
Rationale: SSRIs like sertraline acutely increase synaptic serotonin by blocking the serotonin
transporter (SERT), which initially stimulates excitatory 5-HT2A and 5-HT3 receptors, causing
anxiety, agitation, and gastrointestinal upset before desensitization occurs over 2–4 weeks.
Option A describes the delayed mechanism responsible for the antidepressant effect
(beta-downregulation theory), not the early side effects, and this process takes weeks rather
than days. On the NR 546 exam, expect questions linking acute serotonergic stimulation to
early activation symptoms and distinguishing these from the delayed therapeutic effects that
emerge after receptor adaptation.
Question 4 of 50
, A 56-year-old man with schizophrenia is switched from oral risperidone to long-acting
injectable paliperidone palmitate. The NP reviews the pharmacokinetic profile and notes that
paliperidone is the active metabolite of risperidone formed through which metabolic
pathway?
A. N-dealkylation via CYP2D6
B. Hydroxylation via CYP3A4
C. 9-hydroxylation via CYP2D6 ✓ CORRECT
D. Demethylation via CYP1A2
Correct Answer: C
Rationale: Paliperidone (9-hydroxyrisperidone) is formed through 9-hydroxylation of
risperidone primarily by CYP2D6, which explains why poor CYP2D6 metabolizers may have
higher risperidone levels but lower paliperidone formation when given oral risperidone. Option
B is incorrect because although CYP3A4 plays a minor role in risperidone metabolism, the
conversion to paliperidone is specifically a CYP2D6-mediated hydroxylation at the 9-position.
When switching patients to paliperidone palmitate, remember that this formulation bypasses
first-pass hepatic metabolism, making CYP polymorphisms less clinically relevant than with
oral risperidone.
Question 5 of 50
A 31-year-old woman with major depressive disorder is considering vortioxetine after failing
two SSRI trials. The NP explains that vortioxetine differs from traditional SSRIs through its
multimodal activity, which includes which additional receptor mechanism?
A. Antagonism at 5-HT3, 5-HT7, and partial agonism at 5-HT1A receptors ✓ CORRECT
B. Full agonism at 5-HT2C and antagonism at D3 receptors
C. Inverse agonism at 5-HT2A and partial agonism at M1 receptors
D. Antagonism at H1 histamine and full agonism at 5-HT4 receptors
Correct Answer: A
Rationale: Vortioxetine is a multimodal antidepressant that inhibits serotonin reuptake while
also antagonizing 5-HT3 and 5-HT7 receptors and acting as a partial agonist at 5-HT1A
receptors; this profile may improve cognitive function and reduce nausea compared to pure
SSRIs. Option B is incorrect because vortioxetine does not act as a full 5-HT2C
agonist—rather, it has minimal activity at 5-HT2C, and its pro-cognitive effects are attributed
to 5-HT3 antagonism enhancing acetylcholine and glutamate transmission. On the NR 546
exam, vortioxetine's multimodal mechanism is frequently tested as an example of how
receptor activity beyond SERT inhibition can address cognitive symptoms in depression.
Question 6 of 50
Psychopharmacology Mental Health Official
Practice Exam Actual Exam 2026/2027 with
Detailed Rationales | Complete Exam-Style
Questions | Pass Guaranteed – A+ Graded
══════════════════════════════════════
SECTION 1: NEUROBIOLOGY & PHARMACODYNAMICS Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 34-year-old woman with treatment-resistant depression is being evaluated for
augmentation with brexpiprazole. The psychiatric-mental health NP explains to the patient
that brexpiprazole's therapeutic effect in depression is primarily mediated through which
receptor mechanism?
A. Full antagonism of D2 receptors and inverse agonism at 5-HT2A receptors
B. Partial agonism at D2 and 5-HT1A receptors with antagonism at 5-HT2A receptors ✓
CORRECT
C. Full agonism at D2 receptors and antagonism at H1 receptors
D. Partial agonism at M1 muscarinic receptors and antagonism at alpha-1 adrenergic
receptors
Correct Answer: B
Rationale: Brexpiprazole is a serotonin-dopamine activity modulator (SDAM) that acts as a
partial agonist at D2 and 5-HT1A receptors while antagonizing 5-HT2A receptors; this unique
profile provides antidepressant augmentation with a lower risk of extrapyramidal symptoms
compared to full D2 antagonists. Option A describes the mechanism of aripiprazole, which
shares partial agonist properties but brexpiprazole has a higher affinity for 5-HT1A and lower
intrinsic activity at D2, making it distinct. On the NR 546 exam, always distinguish partial
agonist mechanisms from full antagonism when evaluating second-generation
antipsychotics used as adjunctive therapy.
Question 2 of 50
A 28-year-old man with bipolar disorder is prescribed lithium carbonate 900 mg daily. At his
3-month follow-up, his serum lithium level is 0.4 mEq/L, and he reports continued mood
,cycling. The NP recalls that lithium's mood-stabilizing effect is most closely linked to its
action on which intracellular signaling pathway?
A. Direct inhibition of GABA-A receptor chloride channels
B. Inhibition of inositol monophosphatase and glycogen synthase kinase-3 (GSK-3) ✓
CORRECT
C. Blockade of NMDA receptor calcium influx
D. Activation of adenylyl cyclase and increased cAMP production
Correct Answer: B
Rationale: Lithium exerts its mood-stabilizing effects primarily through inhibition of inositol
monophosphatase, which depletes inositol and dampens phosphoinositide signaling, and
through inhibition of glycogen synthase kinase-3 (GSK-3), which regulates neuroplasticity and
circadian rhythms. Option D is incorrect because lithium actually inhibits adenylyl cyclase
rather than activating it, and this mechanism is more relevant to its adverse effects on
thyroid function than its primary mood-stabilizing action. Remember that lithium has a narrow
therapeutic index (0.6–1.2 mEq/L for acute mania), and levels below 0.6 mEq/L are generally
subtherapeutic for mood stabilization.
Question 3 of 50
A 42-year-old woman with panic disorder is started on sertraline 25 mg daily. After 2 weeks,
she reports increased anxiety and jitteriness. The NP explains that this early activation is
most likely related to sertraline's initial effects on which neurotransmitter system before
downstream adaptive changes occur?
A. Rapid downregulation of beta-adrenergic receptors in the locus coeruleus
B. Acute increase in synaptic serotonin leading to stimulation of 5-HT2A and 5-HT3 receptors
✓ CORRECT
C. Immediate upregulation of GABA-B receptors in the amygdala
D. Delayed inhibition of norepinephrine reuptake in the prefrontal cortex
Correct Answer: B
Rationale: SSRIs like sertraline acutely increase synaptic serotonin by blocking the serotonin
transporter (SERT), which initially stimulates excitatory 5-HT2A and 5-HT3 receptors, causing
anxiety, agitation, and gastrointestinal upset before desensitization occurs over 2–4 weeks.
Option A describes the delayed mechanism responsible for the antidepressant effect
(beta-downregulation theory), not the early side effects, and this process takes weeks rather
than days. On the NR 546 exam, expect questions linking acute serotonergic stimulation to
early activation symptoms and distinguishing these from the delayed therapeutic effects that
emerge after receptor adaptation.
Question 4 of 50
, A 56-year-old man with schizophrenia is switched from oral risperidone to long-acting
injectable paliperidone palmitate. The NP reviews the pharmacokinetic profile and notes that
paliperidone is the active metabolite of risperidone formed through which metabolic
pathway?
A. N-dealkylation via CYP2D6
B. Hydroxylation via CYP3A4
C. 9-hydroxylation via CYP2D6 ✓ CORRECT
D. Demethylation via CYP1A2
Correct Answer: C
Rationale: Paliperidone (9-hydroxyrisperidone) is formed through 9-hydroxylation of
risperidone primarily by CYP2D6, which explains why poor CYP2D6 metabolizers may have
higher risperidone levels but lower paliperidone formation when given oral risperidone. Option
B is incorrect because although CYP3A4 plays a minor role in risperidone metabolism, the
conversion to paliperidone is specifically a CYP2D6-mediated hydroxylation at the 9-position.
When switching patients to paliperidone palmitate, remember that this formulation bypasses
first-pass hepatic metabolism, making CYP polymorphisms less clinically relevant than with
oral risperidone.
Question 5 of 50
A 31-year-old woman with major depressive disorder is considering vortioxetine after failing
two SSRI trials. The NP explains that vortioxetine differs from traditional SSRIs through its
multimodal activity, which includes which additional receptor mechanism?
A. Antagonism at 5-HT3, 5-HT7, and partial agonism at 5-HT1A receptors ✓ CORRECT
B. Full agonism at 5-HT2C and antagonism at D3 receptors
C. Inverse agonism at 5-HT2A and partial agonism at M1 receptors
D. Antagonism at H1 histamine and full agonism at 5-HT4 receptors
Correct Answer: A
Rationale: Vortioxetine is a multimodal antidepressant that inhibits serotonin reuptake while
also antagonizing 5-HT3 and 5-HT7 receptors and acting as a partial agonist at 5-HT1A
receptors; this profile may improve cognitive function and reduce nausea compared to pure
SSRIs. Option B is incorrect because vortioxetine does not act as a full 5-HT2C
agonist—rather, it has minimal activity at 5-HT2C, and its pro-cognitive effects are attributed
to 5-HT3 antagonism enhancing acetylcholine and glutamate transmission. On the NR 546
exam, vortioxetine's multimodal mechanism is frequently tested as an example of how
receptor activity beyond SERT inhibition can address cognitive symptoms in depression.
Question 6 of 50
