Psychopharmacology — MCQs

Psychopharmacology Indian Medical PG Practice Questions and MCQs

Question 171: Neuroleptic malignant syndrome is characterized by all EXCEPT?

A. Hyperthermia
B. Increased blood pressure and heart rate
C. Hypothermia (Correct Answer)
D. Immobility rigidity

Explanation: **Explanation:** Neuroleptic Malignant Syndrome (NMS) is a rare but life-threatening idiosyncratic reaction to antipsychotic medications (neuroleptics), primarily caused by potent **dopamine (D2) receptor blockade** in the nigrostriatal pathway and hypothalamus. **Why Hypothermia is the Correct Answer:** Hypothermia is the opposite of what occurs in NMS. The hallmark of NMS is **Hyperthermia** (Option A). Central dopamine blockade in the hypothalamus disrupts the body's thermoregulatory set-point, leading to severe fever (often >38°C or 100.4°F). Therefore, hypothermia is not a feature of this syndrome. **Analysis of Other Options:** * **Increased BP and Heart Rate (Option B):** Autonomic instability is a core feature of NMS. This manifests as tachycardia, labile blood pressure (hypertension or hypotension), diaphoresis (profuse sweating), and tachypnea. * **Immobility Rigidity (Option D):** Severe "lead-pipe" muscle rigidity is a diagnostic criterion. This intense muscle contraction leads to decreased mobility and can cause **Rhabdomyolysis**, resulting in elevated Creatine Phosphokinase (CPK) levels. **NEET-PG High-Yield Pearls:** * **Mnemonic (FEVER):** **F**ever, **E**ncephalopathy (altered sensorium), **V**itals unstable, **E**levated CPK/Enzymes, **R**igidity. * **Treatment of Choice:** Immediate discontinuation of the offending drug, aggressive cooling, and pharmacological intervention with **Dantrolene** (muscle relaxant) or **Bromocriptine** (dopamine agonist). * **Key Lab Finding:** Significantly elevated **Serum Creatine Phosphokinase (CPK)** and leukocytosis. * **Differential Diagnosis:** Serotonin Syndrome (presents with hyperreflexia and myoclonus, whereas NMS presents with "lead-pipe" rigidity and bradyreflexia).

Question 172: What is the drug of choice for prophylaxis of mania?

A. Lithium (Correct Answer)
B. Haloperidol
C. Clozapine
D. Carbamazepine

Explanation: **Explanation:** **Lithium** is the gold-standard **Drug of Choice (DOC) for the prophylaxis of Bipolar Affective Disorder (BPAD)**, including both manic and depressive episodes. It is a mood stabilizer that effectively reduces the frequency and severity of relapses. For prophylaxis, therapeutic serum lithium levels are maintained between **0.6 – 0.8 mEq/L** (lower than the 0.8 – 1.2 mEq/L required for acute mania). **Analysis of Incorrect Options:** * **B. Haloperidol:** This is a typical antipsychotic used for the **acute management** of manic symptoms (agitation, psychosis) due to its rapid onset. However, it is not used for long-term prophylaxis as it does not stabilize mood and carries a high risk of Extrapyramidal Side Effects (EPS). * **C. Clozapine:** An atypical antipsychotic reserved for **treatment-resistant schizophrenia** or refractory mania. It is not a first-line prophylactic agent due to the risk of agranulocytosis. * **D. Carbamazepine:** An anticonvulsant used as a **second-line** mood stabilizer. It is preferred in "Rapid Cyclers" or patients who do not respond to Lithium, but it is not the primary DOC. **High-Yield Clinical Pearls for NEET-PG:** * **Teratogenicity:** Lithium is associated with **Ebstein’s Anomaly** (atrialization of the right ventricle) if taken during pregnancy. * **Monitoring:** Before starting Lithium, check **Thyroid Function Tests (TFTs)** and **Renal Function Tests (RFTs)**, as it can cause hypothyroidism and nephrogenic diabetes insipidus. * **Narrow Therapeutic Index:** Lithium toxicity occurs >1.5 mEq/L; hemodialysis is the treatment of choice for severe toxicity (>3.5 mEq/L). * **Drug Interactions:** Thiazides, NSAIDs, and ACE inhibitors can increase lithium levels, leading to toxicity.

Question 173: Lithium is used in a pregnant woman. Which of the following congenital anomalies may occur in the fetus?

A. Tetralogy of Fallot
B. Bicuspid atresia
C. Ebstein's anomaly (Correct Answer)
D. Pulmonary stenosis

Explanation: **Explanation:** **Ebstein’s Anomaly** is the classic, high-yield association with **Lithium** use during the first trimester of pregnancy. It is a rare congenital cardiac defect characterized by the downward displacement of the septal and posterior leaflets of the **tricuspid valve** into the right ventricle. This results in "atrialization" of the right ventricle, leading to tricuspid regurgitation and right-sided heart failure. While Lithium is a known teratogen, it is important to note that the absolute risk of Ebstein’s anomaly is relatively low (approximately 1 in 1,000 to 2,000 exposures); however, this still represents a 10–20 fold increase compared to the general population. **Analysis of Incorrect Options:** * **A. Tetralogy of Fallot:** This is the most common cyanotic heart disease but is not specifically linked to Lithium. It is more commonly associated with DiGeorge syndrome or maternal diabetes. * **B. Bicuspid atresia:** (Likely referring to Tricuspid atresia). While Lithium affects the tricuspid valve, it causes displacement (Ebstein’s), not complete failure of the valve to develop (atresia). * **D. Pulmonary stenosis:** This is often seen as a component of other syndromes (like Noonan or Rubella) but is not the primary defect associated with Lithium. **Clinical Pearls for NEET-PG:** 1. **Timing:** The risk is highest during the **first trimester** (organogenesis). 2. **Management:** If a bipolar patient is on Lithium and planning pregnancy, tapering is considered. If already pregnant, fetal echocardiography is recommended at 18–20 weeks. 3. **Breastfeeding:** Lithium is secreted in breast milk; hence, breastfeeding is generally **contraindicated** as it can cause "Floppy Baby Syndrome" in the infant. 4. **Other Teratogens:** Contrast this with **Valproate**, which is associated with **Neural Tube Defects** (e.g., Spina Bifida).

Question 174: A patient presents with complaints of diminished vision. Ophthalmological examination revealed corneal and lenticular opacities. The patient had been prescribed an antipsychotic drug during a previous visit. Which of the following drugs could have caused these symptoms?

A. Thioridazine (Correct Answer)
B. Haloperidol
C. Flupenthixol
D. Pimozide

Explanation: ### Explanation **Correct Option: A. Thioridazine** Thioridazine is a low-potency typical antipsychotic known for specific ocular side effects. The key to this question lies in the anatomical location of the opacities. * **Corneal and Lenticular (Lens) Opacities:** These are classic side effects of **Chlorpromazine** and **Thioridazine**. They typically present as "star-shaped" opacities that are usually asymptomatic but can diminish vision if extensive. * **Retinal Pigmentation:** Thioridazine is uniquely associated with **Retinitis Pigmentosa** (pigmentary retinopathy) when used in high doses (usually >800 mg/day). This can lead to permanent visual loss and "brownish" vision. **Why Incorrect Options are Wrong:** * **B. Haloperidol:** A high-potency typical antipsychotic. It is more commonly associated with Extrapyramidal Side Effects (EPS) rather than ocular opacities. * **C. Flupenthixol:** A thioxanthene derivative used for psychosis and depression. While it can cause blurred vision due to anticholinergic effects, it does not typically cause structural corneal or lenticular opacities. * **D. Pimozide:** Used primarily for Tourette’s syndrome and delusional parasitosis. Its main side effect concern is QTc prolongation rather than ocular toxicity. **High-Yield Clinical Pearls for NEET-PG:** * **Chlorpromazine:** Associated with **blue-grey skin discoloration** and corneal/lens opacities (the "C" in Chlorpromazine for Corneal). * **Thioridazine:** Associated with **Retinal deposits** (the "R" in Thioridazine for Retinal) and has the highest risk of QTc prolongation among typical antipsychotics. * **Mnemonic:** **C**hlorpromazine = **C**orneal/Lens; **T**hioridazine = **T**errible **R**etinopathy. * **Monitoring:** Patients on long-term Thioridazine require periodic fundus examinations.

Question 175: Which drug is associated with a blue-grey skin discoloration?

A. Chlorpromazine (Correct Answer)
B. Risperidone
C. Memantine
D. Clozapine

Explanation: **Explanation:** **Chlorpromazine (Option A)** is a low-potency typical antipsychotic known for causing specific dermatological and ocular side effects. Long-term use at high doses can lead to a characteristic **blue-grey skin discoloration** in sun-exposed areas. This occurs due to the accumulation of drug metabolites and melanin in the dermis. Additionally, chlorpromazine is classically associated with **benign whitish-brown granular deposits** in the anterior lens and posterior cornea (often described as "star-shaped cataracts"). **Why other options are incorrect:** * **Risperidone (Option B):** An atypical antipsychotic primarily associated with hyperprolactinemia (leading to galactorrhea/amenorrhea) and extrapyramidal symptoms at higher doses, but not skin pigmentation. * **Memantine (Option C):** An NMDA receptor antagonist used in Alzheimer’s disease; its side effects are generally neurological (dizziness, confusion) or gastrointestinal. * **Clozapine (Option D):** An atypical antipsychotic famous for **agranulocytosis** (requiring mandatory WBC monitoring), seizures, and hypersalivation, but it does not cause blue-grey skin changes. **High-Yield Clinical Pearls for NEET-PG:** * **Mnemonic for Chlorpromazine (CPZ):** **C**orneal/Lens deposits, **P**igmentation (blue-grey), and **Z**-level (low) potency. * **Thioridazine** (another typical antipsychotic) is associated with **retinitis pigmentosa** (brownish vision), unlike the corneal changes in chlorpromazine. * Other drugs causing blue-grey skin: **Amiodarone** (anti-arrhythmic) and **Silver** (Argyria). * Chlorpromazine is also a first-line pharmacological treatment for **intractable hiccups**.

Question 176: A patient on a typical antipsychotic develops restlessness, typically of the lower limbs. Which drug is used to treat this side effect?

A. Propranolol (Correct Answer)
B. Trihexyphenidyl
C. Quetiapine
D. Dantrolene

Explanation: **Explanation:** The patient is presenting with **Akathisia**, a common extrapyramidal side effect (EPS) of typical antipsychotics. It is characterized by subjective feelings of inner restlessness and an objective inability to sit still, often manifesting as constant pacing or leg movements. **1. Why Propranolol is correct:** **Propranolol**, a non-selective beta-blocker, is the **first-line treatment** for drug-induced akathisia. While the exact pathophysiology is debated, it is believed that beta-adrenergic receptors in the peripheral and central nervous systems play a role in the motor manifestations of restlessness. Propranolol effectively crosses the blood-brain barrier to alleviate these symptoms. **2. Why other options are incorrect:** * **Trihexyphenidyl:** This is an anticholinergic used primarily for *Drug-Induced Parkinsonism* and *Acute Dystonia*. It is generally ineffective for akathisia. * **Quetiapine:** This is an atypical antipsychotic. While switching to an atypical agent may reduce the risk of EPS, it is not the acute treatment for existing akathisia. * **Dantrolene:** This is a muscle relaxant used specifically for **Neuroleptic Malignant Syndrome (NMS)** and Malignant Hyperthermia. **Clinical Pearls for NEET-PG:** * **Akathisia Timing:** Usually occurs within days to weeks of starting or increasing the dose of an antipsychotic. * **Suicidality Link:** Severe akathisia is high-yield because it is associated with increased agitation and potential suicidality if left untreated. * **Second-line treatments:** If beta-blockers are contraindicated (e.g., in asthma), **Benzodiazepines** (like Lorazepam) or **Cyproheptadine** can be used. * **Rule of Thumb:** For *Dystonia/Parkinsonism* → Think Anticholinergics; for *Akathisia* → Think Beta-blockers.

Question 177: Which condition is Methylphenidate the drug of choice for?

A. Obsessive compulsive disorder
B. Attention deficit hyperkinetic disorder (Correct Answer)
C. Enuresis
D. Autism

Explanation: **Explanation:** **Correct Answer: B. Attention deficit hyperkinetic disorder (ADHD)** **Methylphenidate** is a central nervous system (CNS) stimulant and is considered the **first-line pharmacological treatment (Drug of Choice)** for ADHD in both children and adults. It works by blocking the reuptake of **Dopamine and Norepinephrine** (NDRI mechanism) in the synaptic cleft, particularly in the prefrontal cortex. This increases focus, reduces impulsivity, and decreases hyperactivity by enhancing executive function. **Analysis of Incorrect Options:** * **A. Obsessive Compulsive Disorder (OCD):** The drug of choice for OCD is **SSRIs** (e.g., Fluoxetine, Sertraline) or the TCA **Clomipramine**. Stimulants like Methylphenidate can sometimes exacerbate anxiety or tics associated with OCD. * **C. Enuresis:** The drug of choice for nocturnal enuresis is **Desmopressin** (nasal spray/tablet). Historically, Imipramine (a TCA) was used, but it is now a second-line option due to its side-effect profile. * **D. Autism:** There is no "drug of choice" to treat the core symptoms of Autism Spectrum Disorder. Pharmacotherapy is used only for comorbid symptoms; for example, **Risperidone or Aripiprazole** are FDA-approved for irritability and aggression associated with Autism. **High-Yield Clinical Pearls for NEET-PG:** * **Side Effects:** The most common side effects of Methylphenidate are **insomnia and appetite suppression**. A significant long-term concern is **growth retardation** (monitored via growth charts). * **Other Indications:** Methylphenidate is also used as a second-line treatment for **Narcolepsy**. * **Contraindications:** It should be avoided in patients with Glaucoma, symptomatic cardiovascular disease, or a history of Tics/Tourette’s syndrome. * **Non-Stimulant Alternative for ADHD:** **Atomoxetine** (a selective Norepinephrine Reuptake Inhibitor) is the preferred choice if there is a risk of substance abuse or if stimulants are poorly tolerated.

Question 178: Which of the following is a side effect of SNRIs?

A. Premature ejaculation
B. Delayed orgasm (Correct Answer)
C. Cancer
D. Hypotension

Explanation: **Explanation:** **SNRIs (Serotonin-Norepinephrine Reuptake Inhibitors)**, such as Venlafaxine and Duloxetine, increase the synaptic concentration of serotonin. Elevated serotonin levels in the CNS stimulate **5-HT2 receptors**, which inhibits the spinal cord reflexes required for ejaculation and orgasm. Consequently, **delayed orgasm** (anorgasmia) and delayed ejaculation are common side effects of both SSRIs and SNRIs. **Analysis of Options:** * **Option A (Premature ejaculation):** This is incorrect. Because SNRIs delay ejaculation, they are actually used **off-label to treat** premature ejaculation (Dapoxetine, an SSRI, is specifically approved for this). * **Option C (Cancer):** There is no clinical evidence linking SNRIs to an increased risk of malignancy. * **Option D (Hypotension):** This is incorrect. While some antidepressants (like TCAs) cause orthostatic hypotension, SNRIs are associated with **Hypertension**. The "N" in SNRI stands for Norepinephrine; increased noradrenergic activity can lead to dose-dependent increases in blood pressure. **High-Yield Clinical Pearls for NEET-PG:** * **Sexual Dysfunction:** This is the most common reason for long-term non-compliance with SSRIs/SNRIs. To manage this, clinicians may switch the patient to **Bupropion** or **Mirtazapine**, which have minimal sexual side effects. * **Discontinuation Syndrome:** Abrupt withdrawal of SNRIs (especially Venlafaxine) causes "flu-like" symptoms and "electric shock" sensations. * **Duloxetine:** Specifically indicated for painful physical symptoms (diabetic neuropathy, fibromyalgia) alongside depression.

Question 179: Malignant neuroleptic syndrome is caused by:

A. Antidepressants
B. Anxiolytics
C. Antipsychotics (Correct Answer)
D. Antiepileptics

Explanation: **Explanation:** **Neuroleptic Malignant Syndrome (NMS)** is a rare but life-threatening idiosyncratic reaction to **Antipsychotics** (Neuroleptics). The underlying pathophysiology involves a profound **blockade of central Dopamine (D2) receptors** in the nigrostriatal pathway and hypothalamus. This leads to the classic tetrad of clinical features: hyperthermia, "lead-pipe" muscle rigidity, autonomic instability, and altered mental status. * **Why Antipsychotics are correct:** Both typical (e.g., Haloperidol) and atypical antipsychotics (e.g., Risperidone) can trigger NMS. It is most commonly associated with high-potency first-generation agents. * **Why other options are incorrect:** * **Antidepressants:** These are more commonly associated with **Serotonin Syndrome**, which presents with hyperreflexia and myoclonus rather than lead-pipe rigidity. * **Anxiolytics:** Benzodiazepines are actually used in the supportive management of NMS to control agitation and muscle spasms. * **Antiepileptics:** These do not typically cause NMS; however, certain drugs like Carbamazepine can rarely cause Stevens-Johnson Syndrome. **High-Yield Clinical Pearls for NEET-PG:** 1. **Laboratory Hallmark:** Significantly elevated **Creatine Phosphokinase (CPK)** levels due to muscle necrosis (rhabdomyolysis). 2. **Drug of Choice:** **Dantrolene** (a direct-acting muscle relaxant) or **Bromocriptine** (a dopamine agonist). 3. **Differential Diagnosis:** Unlike Serotonin Syndrome (caused by SSRIs), NMS is characterized by **"Lead-pipe" rigidity** and **bradyreflexia**, whereas Serotonin Syndrome features hyperreflexia and tremors. 4. **Non-Antipsychotic Cause:** Sudden withdrawal of anti-Parkinsonian drugs (like Levodopa) can also trigger an NMS-like state.

Question 180: Metabolic syndrome is most commonly associated with which of the following groups of medications as a side effect?

A. Anti-anxiety drugs
B. Antidepressant drugs
C. Antipsychotic drugs (Correct Answer)
D. Anticholinergic drugs

Explanation: **Explanation:** **Metabolic Syndrome** (characterized by weight gain, dyslipidemia, and insulin resistance) is a major adverse effect primarily associated with **Antipsychotic drugs**, particularly the **Second-Generation Antipsychotics (SGAs)** or Atypical Antipsychotics. **Why Antipsychotics are the correct answer:** The underlying mechanism involves the blockade of **Histamine (H1)** and **Serotonin (5-HT2C)** receptors, which leads to increased appetite, sedation, and significant weight gain. Furthermore, these drugs directly interfere with insulin signaling and lipid metabolism. Among SGAs, **Clozapine** and **Olanzapine** carry the highest risk, while Aripiprazole and Ziprasidone are considered metabolic-neutral. **Why other options are incorrect:** * **Anti-anxiety drugs (e.g., Benzodiazepines):** These primarily cause sedation, cognitive impairment, and potential dependence, but do not typically cause metabolic derangements. * **Antidepressant drugs:** While some (like Mirtazapine or TCAs) can cause weight gain, they are not as strongly or universally linked to the full cluster of metabolic syndrome as antipsychotics are. * **Anticholinergic drugs:** These cause "dry" side effects (dry mouth, blurred vision, constipation, urinary retention) and tachycardia, but do not impact glucose or lipid metabolism. **High-Yield Clinical Pearls for NEET-PG:** 1. **Highest Risk:** Clozapine > Olanzapine > Quetiapine. 2. **Lowest Risk:** Aripiprazole, Ziprasidone, Lurasidone. 3. **Monitoring:** Patients on SGAs must have regular monitoring of **BMI, Waist Circumference, Fasting Blood Sugar, and Lipid Profile** (as per ADA/APA guidelines). 4. **Drug of Choice:** If a patient develops metabolic syndrome, switching to a "metabolic-neutral" agent like **Aripiprazole** is often the next step.

Practice by Chapter

Principles of Psychopharmacology

Practice Questions

Antipsychotic Medications

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Antidepressant Medications

Practice Questions

Mood Stabilizers

Practice Questions

Anxiolytics and Hypnotics

Practice Questions

Stimulants and Cognitive Enhancers

Practice Questions

Pharmacokinetics and Pharmacodynamics

Practice Questions

Drug Interactions

Practice Questions

Adverse Effects and Management

Practice Questions

Pharmacogenomics in Psychiatry

Practice Questions

Special Populations Considerations

Practice Questions

Treatment Algorithms and Guidelines

Practice Questions

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