Psychiatric-Mental Health Nurse Practitioner Exam Medications 5

Question 1

A patient with treatment-resistant depression is started on ketamine infusions. Which mechanism best explains its rapid antidepressant effect?

Accepted Answer

NMDA receptor antagonism followed by AMPA receptor upregulation and BDNF release

Answer

Ketamine blocks NMDA receptors, causing a glutamate surge that activates AMPA receptors, releasing BDNF and promoting rapid synaptogenesis in the prefrontal cortex and hippocampus.

Question 2

Which long-acting injectable antipsychotic formulation has the longest dosing interval, allowing once-every-3-month administration?

Accepted Answer

Paliperidone palmitate 3-month (Invega Trinza)

Answer

Paliperidone palmitate 3-month (Invega Trinza) is the only LAI antipsychotic approved for once-every-3-month dosing, improving adherence in stabilized patients.

Question 3

A patient with OCD is not responding to adequate SSRI trials. According to evidence-based guidelines, what is the next pharmacological step?

Accepted Answer

Augment with a low-dose antipsychotic such as risperidone or aripiprazole

Answer

For SSRI-refractory OCD, augmentation with a low-dose D2-blocking antipsychotic (risperidone, aripiprazole, haloperidol) has the strongest evidence and is guideline-recommended.

Question 4

A patient with bipolar depression is prescribed quetiapine. At which dose range does quetiapine primarily exert antidepressant effects versus antipsychotic effects?

Accepted Answer

Low doses (50-150 mg) for antidepressant via H1/5-HT2 blockade; higher doses for antipsychotic via D2 blockade

Answer

At lower doses, quetiapine preferentially blocks H1 and 5-HT2A receptors (contributing to antidepressant/sedating effects); D2 blockade (antipsychotic effect) predominates at higher doses.

Question 5

A patient on disulfiram for alcohol use disorder inadvertently uses an aftershave containing 70% ethanol. What reaction is expected and what is the mechanism?

Accepted Answer

Flushing, nausea, tachycardia, and hypotension due to acetaldehyde accumulation from ALDH inhibition

Answer

Disulfiram inhibits aldehyde dehydrogenase (ALDH), causing acetaldehyde to accumulate when any ethanol source is absorbed, producing the aversive disulfiram-ethanol reaction even from topical exposures.

Psychiatric-Mental Health Nurse Practitioner Exam Practice Test

Psychiatric-Mental Health Nurse Practitioner Exam Practice Test

Psychiatric-Mental Health Nurse Practitioner Exam Medications 5