Psychopharmacology — MCQs

Psychopharmacology Indian Medical PG Practice Questions and MCQs

Question 321: Which of the following is the drug of choice for managing acute mania in bipolar disorder?

A. Lithium (Correct Answer)
B. Valproate
C. Carbamazepine
D. Lamotrigine

Explanation: ***Lithium*** - **Lithium** has historically been considered the **gold standard** and **classical first-line treatment** for acute mania in bipolar disorder, with well-established efficacy in mood stabilization. - It works by modulating **neurotransmitter systems** and **intracellular signaling pathways** (including inhibition of inositol monophosphatase) to reduce manic symptoms. - **Note:** Current guidelines (APA, CANMAT) recognize **multiple first-line options** including lithium, valproate, and antipsychotics, though lithium remains the **prototype mood stabilizer** taught in medical education. - Onset of antimanic effect: **7-14 days**. *Valproate* - **Valproate** (sodium valproate/divalproex) is equally effective for acute mania and is also considered a **first-line agent** in current clinical practice, particularly for **mixed episodes** and **rapid cycling**. - Its mechanism involves increasing **GABA activity** and stabilizing neuronal membranes. - **Faster onset of action** than lithium (within days), making it advantageous in acute settings. - Often preferred when rapid control is needed or in patients with contraindications to lithium. *Carbamazepine* - **Carbamazepine** is an anticonvulsant used as a **mood stabilizer**, particularly for patients who do not respond to lithium or valproate. - It acts by blocking **voltage-gated sodium channels** and enhancing GABAergic transmission. - Considered a **second-line** or **alternative agent** for acute mania due to enzyme induction and drug interactions. *Lamotrigine* - **Lamotrigine** is primarily effective in preventing **depressive episodes** in bipolar disorder and has **minimal to no efficacy** for acute mania. - It works by blocking **voltage-sensitive sodium channels** and inhibiting the release of excitatory neurotransmitters like glutamate. - May even worsen mania or precipitate mixed states; **not indicated** for acute mania treatment.

Question 322: Which selective serotonin reuptake inhibitor (SSRI) is frequently prescribed as the first-line treatment for depression?

A. Amitriptyline
B. Paroxetine
C. Fluoxetine (Correct Answer)
D. Venlafaxine

Explanation: ***Fluoxetine*** - **Fluoxetine** is one of the most widely prescribed **first-line SSRIs** for depression and is frequently chosen in clinical practice. - Its **long half-life (4-6 days for active metabolite norfluoxetine)** reduces risk of discontinuation syndrome and allows for more flexible dosing. - **Activating properties** can be beneficial for patients with psychomotor retardation or fatigue-predominant depression. - Well-established efficacy across depressive and anxiety disorders with extensive clinical experience. *Amitriptyline* - **Amitriptyline** is a **tricyclic antidepressant (TCA)**, not an SSRI. - TCAs are typically **second-line** or reserved for treatment-resistant depression due to significant **anticholinergic effects** (dry mouth, constipation, urinary retention), **cardiovascular side effects** (orthostatic hypotension, arrhythmias), and **higher toxicity in overdose**. - Narrow therapeutic index makes them less safe than SSRIs. *Paroxetine* - **Paroxetine** is also an SSRI and is used as a first-line agent, though it has some distinctive characteristics. - More **sedating** than other SSRIs due to anticholinergic properties, which can be useful for anxious depression but may cause weight gain. - **Shortest half-life** among SSRIs leads to more severe **discontinuation syndrome** if doses are missed. - While effective, it is often not the preferred first choice due to withdrawal concerns and side effect profile. *Venlafaxine* - **Venlafaxine** is a **serotonin-norepinephrine reuptake inhibitor (SNRI)**, not a selective serotonin reuptake inhibitor. - Generally considered when SSRIs are ineffective or for specific indications like severe depression or generalized anxiety disorder. - Can cause **dose-dependent hypertension** and has a more complex side effect profile compared to SSRIs.

Question 323: A 35-year-old woman with major depressive disorder is started on fluoxetine. After two weeks, she develops restlessness, tremors, and hyperreflexia. What is the most likely cause?

A. Neuroleptic malignant syndrome
B. Serotonin syndrome (Correct Answer)
C. Acute dystonia
D. Hypokalemia

Explanation: ***Serotonin syndrome*** - The patient's symptoms of **restlessness**, **tremors**, and **hyperreflexia** after starting **fluoxetine** (an SSRI) are characteristic of **serotonin syndrome**, caused by excessive serotonin activity. - This condition is often precipitated by the introduction of a new serotonergic agent or an increase in the dosage of an existing one. *Neuroleptic malignant syndrome* - Characterized by **severe muscle rigidity**, **fever**, altered mental status, and autonomic instability, often associated with antipsychotic medications. - It does not typically present with the same constellation of motor and reflex symptoms as seen here with an SSRI. *Acute dystonia* - Involves **sustained muscle contractions** causing twisting and repetitive movements or abnormal postures, often occurring shortly after starting or increasing an antipsychotic. - It does not typically include the widespread neurological symptoms like hyperreflexia and generalized tremors observed in this patient. *Hypokalemia* - Can cause **muscle weakness**, cramps, and fatigue, and in severe cases, cardiac arrhythmias. - It does not explain the patient's neurological symptoms like restlessness, tremors, and hyperreflexia after starting fluoxetine.

Question 324: A 35-year-old female with major depressive disorder, who started on an SSRI three weeks ago, now reports increased anxiety, restlessness, insomnia, and thoughts of suicide. Analyze and choose the next step.

A. Urgent psychiatric evaluation and safety assessment. (Correct Answer)
B. Add short-term anxiolytic and urgent psychiatric referral.
C. Continue SSRI and add augmentation therapy with close monitoring.
D. Gradually taper SSRI and monitor closely.

Explanation: ***Urgent psychiatric evaluation and safety assessment.*** - The emergence of **suicidal thoughts** after starting an SSRI is a **psychiatric emergency** requiring immediate safety evaluation and risk assessment. - **SSRI-induced activation syndrome** or paradoxical worsening can occur in the initial weeks, particularly in young adults, with FDA black box warnings about increased suicidal ideation during this period. - **Direct safety assessment** takes priority over all other interventions - the patient needs immediate evaluation for hospitalization, means restriction, and crisis intervention. - Once safety is established, the psychiatrist can then determine whether to continue, adjust, or discontinue the SSRI. *Add short-term anxiolytic and urgent psychiatric referral.* - While this includes **urgent psychiatric referral**, starting a new medication (anxiolytic) before completing a safety assessment could delay critical intervention. - The addition of an anxiolytic doesn't address the **immediate suicidal risk** - safety evaluation must come first, then treatment decisions can be made. *Continue SSRI and add augmentation therapy with close monitoring.* - Continuing the potentially offending agent and adding augmentation without first conducting an **urgent safety assessment** in a patient with suicidal ideation is inappropriate and potentially dangerous. - While activation syndrome symptoms may eventually resolve, **active suicidal thoughts** require immediate psychiatric evaluation, not outpatient medication adjustment. *Gradually taper SSRI and monitor closely.* - Any medication changes, including tapering, should only occur **after comprehensive psychiatric evaluation and safety assessment**. - Abrupt or premature discontinuation of SSRIs can cause **discontinuation syndrome** and may worsen the clinical picture. - "Monitor closely" is insufficient for a patient with **active suicidal ideation** - immediate psychiatric intervention is required.

Question 325: A female patient on lithium for bipolar disorder for 6 months presents with seizures, tremors, confusion, and weakness. What is the primary investigation to diagnose lithium toxicity?

A. serum electrolytes
B. serum lithium level (Correct Answer)
C. ECG
D. MRI

Explanation: ***Serum lithium level*** - An elevated **serum lithium level** is the definitive diagnostic test for lithium toxicity, directly measuring the concentration of the drug in the patient's blood. - The symptoms of seizures, tremors, confusion, and weakness are all classic signs of **lithium neurotoxicity**, making the measurement of its blood concentration critical. - Therapeutic range: 0.6-1.2 mEq/L; toxicity typically occurs at levels >1.5 mEq/L. *Serum electrolytes* - While lithium toxicity can affect **electrolyte balance** (e.g., causing hyponatremia due to renal effects), measuring electrolytes alone is not sufficient to diagnose lithium toxicity. - Electrolytes should be checked as **dehydration and hyponatremia can precipitate toxicity**, but they don't directly measure lithium concentration. - Changes in electrolytes are often secondary and not directly indicative of the circulating **lithium concentration**. *ECG* - An **ECG** can reveal cardiac effects of lithium toxicity, such as **T-wave inversions** or **QT prolongation**, but it does not directly measure lithium levels or confirm the diagnosis. - Cardiac abnormalities are usually seen in severe toxicity and are not the primary diagnostic marker. - ECG is important for monitoring cardiac complications but is not diagnostic of lithium toxicity itself. *MRI* - An **MRI of the brain** might be considered in cases of severe neurological symptoms like seizures or altered mental status to rule out other causes or assess for **cerebral edema**, but it does not diagnose lithium toxicity itself. - It is a supportive or exclusionary test, not the primary diagnostic tool for lithium overdose.

Question 326: What is the classical drug of choice for Tourette syndrome?

A. Haloperidol (Correct Answer)
B. Amantadine
C. Propranolol
D. Diazepam

Explanation: ***Haloperidol*** - **Haloperidol**, a **first-generation antipsychotic**, is highly effective in blocking dopamine receptors and reducing the frequency and severity of tics in Tourette syndrome. - Its efficacy in managing severe tics makes it a **classical drug of choice**, particularly for individuals who do not respond to less potent interventions. *Amantadine* - **Amantadine** is primarily used as an **antiviral agent** against influenza A and as an antiparkinsonian drug, enhancing dopamine release. - It is not indicated for the treatment of Tourette syndrome as its mechanism of action is related to increasing dopamine, which would worsen tics. *Propranolol* - **Propranolol** is a **beta-blocker** primarily used to treat conditions like hypertension, angina, and essential tremor by reducing adrenergic activity. - While it can help with anxiety and some motor symptoms in specific conditions, it is not a primary treatment for the motor and vocal tics characteristic of Tourette syndrome. *Diazepam* - **Diazepam** is a **benzodiazepine** that acts as a central nervous system depressant, used primarily for anxiety, insomnia, and muscle spasms. - While it can help with associated anxiety, it does not directly address the underlying mechanism of tics in Tourette syndrome and is not a drug of choice for tic management.

Question 327: What is the treatment of choice for akathisia?

A. Benztropine
B. Propranolol (Correct Answer)
C. Dantrolene
D. Lithium

Explanation: ***Propranolol*** - **Beta-blockers** like propranolol are considered first-line treatment for akathisia due to their ability to reduce central as well as peripheral noradrenergic hyperactivity and anxiety. - They are particularly effective in alleviating the subjective feeling of **inner restlessness** and the objective motor symptoms, especially when the akathisia is induced by antipsychotics. *Benztropine* - This is an **anticholinergic** medication primarily used to treat other extrapyramidal symptoms like **dystonia** and **pseudoparkinsonism**. - While it might provide some relief for certain motor aspects, it is generally less effective for the subjective feeling of restlessness in akathisia and can have significant side effects. *Dantrolene* - **Dantrolene** is a direct-acting **skeletal muscle relaxant** used primarily in the treatment of **neuroleptic malignant syndrome (NMS)** and malignant hyperthermia. - It is not indicated for the management of extrapyramidal symptoms like akathisia. *Lithium* - **Lithium** is a mood stabilizer used predominantly in the treatment of **bipolar disorder**. - It has no role in the direct treatment of akathisia; however, it can ironically sometimes induce or worsen akathisia as a side effect itself.

Question 328: Which of the following is the preferred first-line pharmacological treatment for tardive dyskinesia?

A. Tetrabenazine
B. Baclofen
C. Cessation of antipsychotic medication
D. Valbenazine (Correct Answer)

Explanation: ***Valbenazine*** - **Valbenazine** is a **VMAT2 inhibitor** approved by the FDA as a **first-line treatment** for tardive dyskinesia. - It works by reducing **presynaptic dopamine release**, thereby mitigating involuntary movements. - Along with deutetrabenazine, it represents the **preferred pharmacological approach** for tardive dyskinesia, with good efficacy and tolerability. *Tetrabenazine* - **Tetrabenazine** is also a **VMAT2 inhibitor** that reduces dopamine levels. - However, the **newer VMAT2 inhibitors** (valbenazine and deutetrabenazine) are generally **preferred as first-line** due to **better tolerability** (lower risk of depression, parkinsonism, and somnolence) and simpler dosing schedules. - Tetrabenazine may still be used when newer agents are unavailable. *Baclofen* - **Baclofen** is a **GABA-B receptor agonist** primarily used for spasticity and muscle rigidity. - While it has been explored for tardive dyskinesia, it is **not considered first-line** pharmacological treatment due to **limited efficacy** compared to VMAT2 inhibitors. *Cessation of antipsychotic medication* - While sometimes considered, outright **cessation** of antipsychotic medication is often **not feasible** or desirable due to the risk of **relapse of underlying psychiatric illness**. - It can sometimes even **worsen tardive dyskinesia symptoms** temporarily (withdrawal-emergent dyskinesia). - The first-line approach involves **pharmacological treatment with VMAT2 inhibitors** to manage the dyskinesia while maintaining psychiatric stability.

Question 329: Which of the following conditions is a contraindication for ECT?

A. Raised ICT (Correct Answer)
B. Severe medical illness
C. Severe heart disease
D. Pregnancy complications

Explanation: ***Raised ICT*** - **Raised intracranial tension (ICT)** is an absolute contraindication for ECT due to the transient increase in **cerebral blood flow** and pressure during the procedure. - This increase in pressure can lead to **brain herniation** or further neurological compromise in patients with pre-existing elevated ICT. *Severe medical illness* - While severe medical illness can pose a risk, it is generally considered a **relative contraindication** rather than an absolute one. - The decision to proceed with ECT in such cases involves a careful **risk-benefit analysis** and close monitoring. *Severe heart disease* - **Severe heart disease**, such as **unstable angina** or **recent myocardial infarction**, is a relative contraindication. - It requires careful cardiac evaluation and management, but does not absolutely preclude ECT if the benefits outweigh the risks. *Pregnancy complications* - **Pregnancy** itself is not a contraindication for ECT; in some cases, it may be the preferred treatment for severe psychiatric illness during pregnancy. - However, complications might necessitate careful monitoring and adjustment of the procedure.

Question 330: Psychotic patient on antipsychotic drugs develops torticollis within 4 days of therapy. What is the treatment?

A. Peripheral anticholinergic drugs
B. Beta blockers
C. Dantrolene
D. Central anticholinergic drugs (Correct Answer)

Explanation: ***Central anticholinergic drugs*** - The patient is experiencing an **acute dystonic reaction**, a common extrapyramidal side effect of antipsychotics, such as **torticollis**, which requires immediate treatment with central anticholinergic agents. - Medications like **benztropine** or **diphenhydramine** are indicated to quickly reverse these symptoms by blocking acetylcholine activity in the basal ganglia. *Peripheral anticholinergic drugs* - These agents primarily act outside the central nervous system and are not effective in treating centrally mediated extrapyramidal symptoms like **acute dystonia**. - Their main use is for conditions like **bradycardia** or to reduce **gastrointestinal motility**. *Beta blockers* - **Beta-blockers** are primarily used to treat **akathisia** (restlessness) associated with antipsychotic medication, not acute dystonic reactions like torticollis. - They work by reducing the somatic manifestations of anxiety and motor restlessness. *Dantrolene* - **Dantrolene** is a **direct skeletal muscle relaxant** primarily used in the treatment of **neuroleptic malignant syndrome** or **malignant hyperthermia**. - It is not the first-line treatment for acute dystonic reactions as it does not address the underlying neurochemical imbalance.

Practice by Chapter

Principles of Psychopharmacology

Practice Questions

Antipsychotic Medications

Practice Questions

Antidepressant Medications

Practice Questions

Mood Stabilizers

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Anxiolytics and Hypnotics

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Stimulants and Cognitive Enhancers

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Pharmacokinetics and Pharmacodynamics

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Drug Interactions

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Adverse Effects and Management

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Pharmacogenomics in Psychiatry

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Special Populations Considerations

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Treatment Algorithms and Guidelines

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