Drugs in Psychiatric Disorders Practice Questions

Q: Which of the following antipsychotics is known to increase prolactin secretion?

Risperidone. ***Risperidone*** - **Risperidone** has a high affinity for **D2 dopamine receptors** in the tuberoinfundibular pathway, which leads to significant **prolactin elevation**. - **Dopamine** typically inhibits prolactin release; blocking D2 receptors disinhibits this process, causing increased secretion. *Olanzapine* - **Olanzapine** is a **second-generation antipsychotic** that generally causes **less prolactin elevation** compared to risperidone. - Its D2 receptor antagonism is transient or weaker in the tuberoinfundibular pathway, allowing less significant impact on prolactin. *Ziprasidone* - **Ziprasidone** is known for its **low risk of prolactin elevation** compared to other antipsychotics. - It has a unique receptor binding profile that includes 5-HT1A agonism and moderate D2 antagonism, which mitigates prolactin increase. *Clozapine* - **Clozapine** is associated with a **very low risk of prolactin elevation** and is often used in patients who experience prolactin-related side effects with other antipsychotics. - Its **weak and transient D2 receptor blockade** in the tuberoinfundibular pathway explains its minimal impact on prolactin levels.

Q: Most common renal sequela of lithium toxicity is?

Nephrogenic Diabetes Insipidus. ***Nephrogenic Diabetes Insipidus*** - **Lithium** interferes with the action of **ADH** on the renal tubules, specifically at the **collecting ducts**, leading to an inability to concentrate urine. - This results in **polyuria** (excessive urination) and **polydipsia** (excessive thirst), characteristic symptoms of **nephrogenic diabetes insipidus**. *Renal tubular acidosis* - While lithium can affect tubular function, **renal tubular acidosis** is less common than nephrogenic diabetes insipidus. - RTA involves impaired acid excretion or bicarbonate reabsorption, leading to **metabolic acidosis**. *Glycosuria* - **Glycosuria** (glucose in urine) is primarily associated with **diabetes mellitus** or other conditions affecting glucose reabsorption in the proximal tubule. - Lithium toxicity does not typically cause glycosuria. *MPGN* - **Membranoproliferative glomerulonephritis (MPGN)** is a type of glomerular injury characterized by specific changes in the glomerulus. - MPGN is not directly caused by **lithium toxicity**; lithium primarily affects tubular function rather than glomerular structure.

Q: At which receptor is the primary action of antipsychotic medications required?

D2 dopaminergic. ***D2 dopaminergic*** - The **antipsychotic effects** of typical (first-generation) antipsychotics are primarily mediated through **D2 receptor blockade** [1]. - Blocking D2 receptors in the **mesolimbic pathway** helps reduce positive symptoms of psychosis like hallucinations and delusions [2]. *M, muscarinic* - **Muscarinic receptor blockade** is a common adverse effect of some antipsychotics, leading to anticholinergic side effects such as **dry mouth** and **blurred vision**, rather than their primary therapeutic action. - This action does not directly contribute to the antipsychotic effect. *D1 dopaminergic* - While D1 receptors are involved in dopamine signaling, they are **not the primary target** for the antipsychotic action of most drugs [1]. - Some atypical antipsychotics may affect D1 receptors, but it's secondary to their D2 antagonism and serotonin modulation. *5HT4 serotonergic* - **Serotonin receptors (5HT)**, particularly 5HT2A, are important targets for atypical (second-generation) antipsychotics. - However, 5HT4 receptors are **not a primary target** for the antipsychotic effects, and 5HT2A blockade modulates dopamine release, which is still connected to the D2 hypothesis.

Q: Which of the following is NOT a known side effect of lithium?

Hyperthyroidism. ***Hyperthyroidism*** - Lithium commonly causes **hypothyroidism** by interfering with thyroid hormone synthesis and release, not hyperthyroidism. - Patients on lithium often require **thyroid function monitoring** and may need thyroid hormone supplementation. *Polyuria* - **Nephrogenic diabetes insipidus**, characterized by polyuria and polydipsia, is a common side effect of lithium. - Lithium interferes with the kidney's ability to respond to **vasopressin (ADH)**, leading to increased water excretion. *Nephropathy* - Chronic lithium use can lead to **interstitial nephropathy**, characterized by a reduction in glomerular filtration rate. - Long-term monitoring of **renal function** is crucial for patients on lithium therapy. *Ebstein's anomaly* - While not a general "side effect" in adults, **Ebstein's anomaly** is a congenital heart defect associated with lithium exposure during the first trimester of pregnancy. - It involves displacement of the **tricuspid valve leaflets** into the right ventricle.

Q: Antidepressant drug used in nocturnal enuresis is:

Imipramine. ***Imipramine*** - **Imipramine**, a **tricyclic antidepressant (TCA)**, is frequently used off-label for **nocturnal enuresis** in children [1]. - Its mechanism of action in enuresis is thought to involve a combination of anticholinergic effects (which relax the bladder detrusor muscle) and central nervous system effects (which may increase bladder capacity and arousal from sleep) [1]. *Fluoxetine* - **Fluoxetine** is a **selective serotonin reuptake inhibitor (SSRI)** and is primarily used for depression, anxiety disorders, and OCD [2]. - It is not indicated for the treatment of nocturnal enuresis and does not have the same bladder-relaxing or arousal-modulating properties as imipramine in this context. *Trazodone* - **Trazodone** is a **serotonin antagonist and reuptake inhibitor (SARI)**, commonly prescribed for depression and insomnia due to its prominent sedative effects. - It is not used for nocturnal enuresis and its mechanism of action does not confer benefits for bladder control. *Sertraline* - **Sertraline** is another **selective serotonin reuptake inhibitor (SSRI)** used for a wide range of psychiatric conditions, including depression, anxiety, and panic disorder [2]. - Like fluoxetine, it is not an appropriate treatment for nocturnal enuresis and lacks the specific known effects beneficial for this condition.

Q: Which of the following is the most characteristic sexual side effect of SSRIs?

Delayed ejaculation. ***Delayed ejaculation*** - **Delayed ejaculation** is a common and characteristic sexual side effect of SSRIs due to their impact on serotonin pathways involved in sexual response. - This effect can lead to significant distress and non-adherence to treatment, and often requires dose adjustment or switching to an alternative antidepressant. *Erectile dysfunction* - While **erectile dysfunction** can occur with SSRIs, it is a less specific and less consistently reported sexual side effect compared to ejaculatory dysfunction. - Many factors, including underlying mood disorder and comorbidities, can contribute to erectile dysfunction, making it less characteristic of SSRI use alone. *Retrograde ejaculation* - **Retrograde ejaculation** is a condition where semen enters the bladder during orgasm, and while it can be a side effect of some medications (e.g., alpha-blockers), it is not a hallmark sexual side effect of SSRIs. - SSRIs primarily affect the process of emission and expulsion, leading more commonly to delayed or absent ejaculation rather than retrograde flow. *Anxiety* - **Anxiety** is generally a *primary symptom* of the conditions SSRIs are prescribed to treat, such as depression or anxiety disorders, not a sexual side effect of the medication itself. - Although SSRIs can initially cause or worsen anxiety in some patients before therapeutic effects are seen, this is a systemic side effect, not a sexual one.

Q: Which anxiolytic acts through 5-HT1A receptor partial agonism without exhibiting significant anticonvulsant or muscle relaxant properties?

Buspirone. ***Buspirone*** - **Buspirone** is a unique anxiolytic that primarily acts as a **partial agonist at 5-HT1A receptors**. - Unlike benzodiazepines, it lacks significant **anticonvulsant**, **muscle relaxant**, or **sedative-hypnotic properties** and does not lead to physical dependence or withdrawal. *Diazepam* - **Diazepam** is a **benzodiazepine** that acts by enhancing the effect of **GABA** at GABA-A receptors, leading to significant anxiolytic, sedative, muscle relaxant, and anticonvulsant effects. - It does not primarily act via **5-HT1A receptor partial agonism**. *Zolpidem* - **Zolpidem** is a **non-benzodiazepine hypnotic** that selectively binds to the **GABA-A receptor** subunit, primarily mediating sedative effects. - While it's used for insomnia, it doesn't primarily act as a **5-HT1A partial agonist** and is not typically used for its anxiolytic properties in the same way as buspirone. *Phenobarbitone* - **Phenobarbitone** is a **barbiturate** that acts by prolonging the opening of **chloride channels** associated with GABA-A receptors, leading to strong sedative, hypnotic, and anticonvulsant effects. - Its mechanism of action is distinct from **5-HT1A receptor partial agonism**, and it carries a high risk of dependence and overdose.

Q: Which of the following is a tricyclic antidepressant?

Doxepin. ***Doxepin*** - **Doxepin** is a **tricyclic antidepressant (TCA)** that inhibits the reuptake of **serotonin** and **norepinephrine**, and also has significant **histaminergic** and **cholinergic** blocking effects. - TCAs, including doxepin, are commonly used for treating **depression**, **anxiety**, and certain pain conditions. *Venlafaxine* - **Venlafaxine** is a **serotonin-norepinephrine reuptake inhibitor (SNRI)**, not a tricyclic antidepressant. - SNRIs selectively block the reuptake of both **serotonin** and **norepinephrine**, but lack the broad receptor affinity of TCAs. *Fluoxetine* - **Fluoxetine** is a **selective serotonin reuptake inhibitor (SSRI)**, which specifically targets serotonin reuptake. - SSRIs are generally considered a first-line treatment for depression due to a more favorable side effect profile compared to TCAs. *Citalopram* - **Citalopram** is also a **selective serotonin reuptake inhibitor (SSRI)**, much like fluoxetine. - It works by increasing the levels of **serotonin** in the brain by blocking its reuptake, differentiating it from tricyclic antidepressants.

Q: Which of the following is an antipsychotic drug?

Flupenthixol. ***Flupenthixol*** - **Flupenthixol** is a **first-generation (typical) antipsychotic** used primarily for managing **schizophrenia** and other psychotic disorders. - It acts by blocking **dopamine D2 receptors** in the brain, reducing positive symptoms like **hallucinations and delusions**. *Rasagiline* - **Rasagiline** is a **monoamine oxidase-B (MAO-B) inhibitor** used in the treatment of **Parkinson's disease**. - It works by preventing the breakdown of **dopamine** in the brain, thereby improving motor symptoms, and is not an antipsychotic. *Clobazam* - **Clobazam** is a **benzodiazepine** primarily indicated for the treatment of **epilepsy** (specifically Lennox-Gastaut syndrome) and **anxiety**. - Its mechanism involves enhancing the effect of **GABA** in the brain, producing sedative and anticonvulsant effects, distinct from antipsychotic action. *Divalproex* - **Divalproex** is a combination product of **valproic acid** and **sodium valproate**, typically used as a **mood stabilizer** for **bipolar disorder**, an **antiepileptic**, and for **migraine prophylaxis**. - It modulates **GABAergic** transmission and sodium channels, but it is not classified as an antipsychotic drug.

Q: Lithium directly affects which ion ?

Sodium. ***Sodium*** - Lithium directly interferes with **sodium ion transport** across cell membranes, particularly by inhibiting the **Na+/K+-ATPase** pump. - This interference alters intracellular sodium concentrations and affects neural excitability, contributing to its **mood-stabilizing** effects. *Potassium* - While potassium transport is linked to the **Na+/K+-ATPase pump**, lithium primarily acts through its effect on **sodium transport**, rather than directly mimicking or significantly altering potassium. - Changes in potassium levels due to lithium are largely secondary to its primary impact on sodium. *Magnesium* - Lithium has a more direct impact on **sodium channels** and transporters, contrasting with its less direct or significant interaction with magnesium metabolism. - Though magnesium is crucial for numerous cellular processes, it is not the primary ion directly affected by lithium's therapeutic actions. *Calcium* - Lithium does not directly affect **calcium channels** or calcium signaling pathways in the same way it impacts sodium. - While lithium may indirectly influence calcium-dependent processes, its primary direct target for therapeutic effects is not calcium.

Question 1

Which of the following antipsychotics is known to increase prolactin secretion?

Accepted Answer

Risperidone

Answer

Olanzapine

Answer

Ziprasidone

Answer

Clozapine

Question 2

Most common renal sequela of lithium toxicity is?

Accepted Answer

Nephrogenic Diabetes Insipidus

Answer

Renal tubular acidosis

Answer

Glycosuria

Answer

MPGN

Question 3

At which receptor is the primary action of antipsychotic medications required?

Accepted Answer

D2 dopaminergic

Answer

M, muscarinic

Answer

5HT4 serotonergic

Answer

D1 dopaminergic

Question 4

Which of the following is NOT a known side effect of lithium?

Accepted Answer

Hyperthyroidism

Answer

Polyuria

Answer

Nephropathy

Answer

Ebstein's anomaly

Question 5

Antidepressant drug used in nocturnal enuresis is:

Accepted Answer

Imipramine

Answer

Fluoxetine

Answer

Trazodone

Answer

Sertraline

Question 6

Which of the following is the most characteristic sexual side effect of SSRIs?

Accepted Answer

Delayed ejaculation

Answer

Retrograde ejaculation

Answer

Erectile dysfunction

Answer

Anxiety

Question 7

Which anxiolytic acts through 5-HT1A receptor partial agonism without exhibiting significant anticonvulsant or muscle relaxant properties?

Accepted Answer

Buspirone

Answer

Diazepam

Answer

Zolpidem

Answer

Phenobarbitone

Question 8

Which of the following is a tricyclic antidepressant?

Accepted Answer

Doxepin

Answer

Fluoxetine

Answer

Citalopram

Answer

Venlafaxine

Question 9

Which of the following is an antipsychotic drug?

Accepted Answer

Flupenthixol

Answer

Rasagiline

Answer

Clobazam

Answer

Divalproex

Question 10

Lithium directly affects which ion ?

Accepted Answer

Sodium

Answer

Potassium

Answer

Magnesium

Answer

Calcium

Drugs in Psychiatric Disorders — MCQs

Drugs in Psychiatric Disorders — MCQs

On this page

Practice by Chapter

Want unlimited practice?