Psychopharmacology — MCQs

A 30-year-old man with schizophrenia has been very withdrawn and apathetic for more than 10 years. He is currently taking an antipsychotic agent that is helping him to be more outgoing and sociable. However, the patient is experiencing seizures and agranulocytosis. Which antipsychotic agent is this patient most likely to be taking?

Q240Easy

Which of the following is an example of an atypical antipsychotic?

Psychopharmacology Indian Medical PG Practice Questions and MCQs

Question 231: What is the prophylactic maintenance serum level of lithium?

A. 0.5 - 0.8 mEq/L (Correct Answer)
B. 0.7 - 1.2 mEq/L
C. 1.2 - 2.0 mEq/L
D. 2.0 - 2.5 mEq/L

Explanation: Lithium is a mood stabilizer with a narrow therapeutic index, meaning the margin between a therapeutic dose and a toxic dose is very small. Monitoring serum levels is critical for safety and efficacy. **Explanation of the Correct Answer:** * **Option A (0.5 – 0.8 mEq/L):** This is the standard range for **prophylactic maintenance** in patients with Bipolar Disorder who are currently stable. Maintaining levels at the lower end of the therapeutic spectrum minimizes long-term side effects (like renal or thyroid toxicity) while preventing future manic or depressive episodes. **Explanation of Incorrect Options:** * **Option B (0.7 – 1.2 mEq/L):** This range is typically reserved for the **Acute Manic Phase**. During an active episode, higher concentrations are required to achieve clinical stabilization. * **Option C (1.2 – 2.0 mEq/L):** This range indicates **Mild to Moderate Toxicity**. Patients may present with coarse tremors, vomiting, diarrhea, and ataxia. * **Option D (2.0 – 2.5 mEq/L):** This indicates **Severe Toxicity**. It is a medical emergency that can lead to seizures, coma, and death. Hemodialysis is often indicated if levels exceed 2.5 mEq/L (or 4.0 mEq/L in chronic users). **High-Yield Clinical Pearls for NEET-PG:** * **Sampling Time:** Serum levels should be measured **12 hours after the last dose** (Trough level). * **Steady State:** It takes approximately **5 days** (5 half-lives) to reach a steady state after starting or changing a dose. * **Teratogenicity:** Lithium is associated with **Ebstein’s Anomaly** (atrialization of the right ventricle) if taken during the first trimester. * **Drug Interactions:** Thiazides, NSAIDs, and ACE inhibitors can **increase** lithium levels, leading to toxicity.

Question 232: Deep brain stimulation has been approved for the treatment of which of the following conditions?

A. Movement disorders like Parkinsonism (Correct Answer)
B. Schizophrenia
C. Depression
D. Anxiety disorder

Explanation: **Explanation:** **Deep Brain Stimulation (DBS)** is a neurosurgical procedure involving the implantation of electrodes in specific brain regions, which are connected to a pulse generator (IPG). It acts as a "brain pacemaker," modulating abnormal neural circuits through electrical impulses. **Why Option A is Correct:** DBS is a well-established, FDA-approved treatment for **Movement Disorders**, particularly when symptoms are no longer adequately controlled by medications. Key targets include: * **Parkinson’s Disease:** Subthalamic Nucleus (STN) or Globus Pallidus interna (GPi). * **Essential Tremor:** Ventral Intermediate Nucleus (VIM) of the Thalamus. * **Dystonia:** Globus Pallidus interna (GPi). **Why Other Options are Incorrect:** * **B. Schizophrenia:** DBS is currently experimental for schizophrenia. There is no standard clinical approval for its use in treating psychosis. * **C. Depression:** While DBS for Treatment-Resistant Depression (targeting the Subgenual Cingulate Cortex/Area 25) is being heavily researched, it is **not yet routinely approved** or considered first-line. (Note: ECT and rTMS are the standard neuromodulation therapies for depression). * **D. Anxiety Disorder:** DBS is not a standard treatment for generalized anxiety. However, it has received **Humanitarian Device Exemption (HDE)** for severe, refractory **Obsessive-Compulsive Disorder (OCD)**, targeting the Internal Capsule. **High-Yield Clinical Pearls for NEET-PG:** * **OCD:** The only psychiatric condition where DBS has a specific (HDE) approval for refractory cases. * **Vagus Nerve Stimulation (VNS):** Approved for refractory Epilepsy and Treatment-Resistant Depression. * **Transcranial Magnetic Stimulation (rTMS):** Non-invasive; approved for Depression and OCD. * **Most common target for Parkinson's DBS:** Subthalamic Nucleus (STN).

Question 233: Antipsychotic-induced akathisia is characterized by which of the following manifestations?

A. Rigidity
B. Tremor
C. Spasm of a muscle or muscle group
D. Restlessness (Correct Answer)

Explanation: **Explanation:** **Akathisia** is the most common extrapyramidal side effect (EPS) associated with antipsychotic medication. It is characterized by a subjective feeling of **inner restlessness** and an objective need to be in constant motion. Patients often describe it as a "desire to jump out of one's skin." Clinically, this manifests as pacing, shifting weight from foot to foot, or inability to sit still. **Why the other options are incorrect:** * **A. Rigidity:** This is a feature of **Drug-Induced Parkinsonism** (often described as "lead-pipe" or "cogwheel" rigidity) or Neuroleptic Malignant Syndrome (NMS). * **B. Tremor:** A rhythmic, oscillatory movement (typically a resting tremor) is another hallmark of **Drug-Induced Parkinsonism**, not akathisia. * **C. Spasm of a muscle group:** This describes **Acute Dystonia**, which involves sudden, involuntary contractions of muscles (e.g., torticollis, oculogyric crisis). Dystonia typically occurs within hours to days of starting medication, whereas akathisia usually appears within days to weeks. **High-Yield Clinical Pearls for NEET-PG:** * **Mechanism:** Thought to be due to dopamine (D2) blockade in the nigrostriatal pathway. * **Management:** The first-line treatment for akathisia is **Beta-blockers (Propranolol)**. Centrally acting anticholinergics (like Benztropine) or Benzodiazepines may also be used, but are generally less effective than Propranolol. * **Clinical Significance:** Akathisia is highly distressing and is a major cause of non-compliance and increased suicide risk in patients on antipsychotics.

Question 234: A patient diagnosed with Schizophrenia and exhibiting violent behavior and agitation is being treated with haloperidol. The patient subsequently develops rigidity and inability to move their eyes. Which of the following medications should be administered intravenously to manage these new symptoms?

A. Diazepam
B. Risperidone
C. Promethazine (Correct Answer)
D. Haloperidol

Explanation: ### Explanation **Concept: Acute Dystonia** The patient is experiencing **Acute Dystonia**, a common Extrapyramidal Side Effect (EPS) of high-potency first-generation antipsychotics like Haloperidol. The "rigidity" and "inability to move eyes" (specifically **Oculogyric Crisis**) result from a sudden dopamine-acetylcholine imbalance in the nigrostriatal pathway, leading to excessive cholinergic activity. **Why Promethazine is Correct:** The management of acute dystonia requires an **anticholinergic agent**. Promethazine is a first-generation antihistamine with potent central anticholinergic properties. When administered intravenously (or intramuscularly), it rapidly restores the dopamine-acetylcholine balance, relieving the muscle spasms. Other standard treatments include Benztropine or Diphenhydramine. **Analysis of Incorrect Options:** * **A. Diazepam:** While a benzodiazepine can help with general agitation or muscle relaxation, it is not the specific antidote for the cholinergic excess seen in dystonia. * **B. Risperidone:** This is an atypical antipsychotic. Adding another antipsychotic would worsen the blockade of D2 receptors and potentially exacerbate EPS. * **D. Haloperidol:** This is the offending agent. Administering more would worsen the patient's condition and increase the risk of Neuroleptic Malignant Syndrome (NMS). **High-Yield NEET-PG Pearls:** * **Acute Dystonia:** Occurs within hours to days of starting treatment (the "4-hour" rule). * **Oculogyric Crisis:** A specific type of dystonia where the eyes are fixed upward; it is a medical emergency due to patient distress. * **Risk Factors:** Young males and those receiving high-potency neuroleptics are at highest risk. * **Prophylaxis:** In clinical practice, Promethazine is often co-administered with Haloperidol injections to prevent these reactions.

Question 235: Which of the following medications is NOT used for the management of tardive dyskinesia?

A. Fluphenazine (Correct Answer)
B. Clozapine
C. Vitamin E
D. Quetiapine

Explanation: **Explanation:** **Tardive Dyskinesia (TD)** is a delayed-onset extrapyramidal side effect caused by the long-term blockade of dopamine (D2) receptors, leading to **dopamine receptor supersensitivity** in the nigrostriatal pathway. **1. Why Fluphenazine is the Correct Answer:** Fluphenazine is a **high-potency, first-generation (typical) antipsychotic**. Because it is a potent D2 receptor antagonist, it is a primary **cause** of tardive dyskinesia. While increasing the dose of a typical antipsychotic might temporarily "mask" TD symptoms by blocking the supersensitive receptors, it ultimately worsens the underlying pathology. Therefore, it is never used as a treatment. **2. Analysis of Other Options:** * **Clozapine:** This is the drug of choice for patients with severe TD who still require antipsychotic treatment. It has low D2 affinity and rapid dissociation, which helps in the gradual reversal of receptor supersensitivity. * **Quetiapine:** Similar to clozapine, quetiapine is a second-generation antipsychotic with low D2 receptor binding potential and is considered a safe alternative when TD develops. * **Vitamin E:** It is often used as an adjunctive treatment based on the theory that free radical damage contributes to the neurotoxicity seen in TD. **Clinical Pearls for NEET-PG:** * **First-line treatment for TD:** Valbenazine or Deutetrabenazine (VMAT2 inhibitors). * **Risk Factors:** Old age, female gender, and long-term use of typical antipsychotics (e.g., Haloperidol, Fluphenazine). * **Clinical Feature:** Choreoathetoid movements, most commonly involving the mouth and tongue (oro-facial dyskinesia). * **Management Strategy:** Prevention is key. If TD occurs, the first step is to reduce the dose or switch to Clozapine/Quetiapine.

Question 236: A patient with schizophrenia who is currently on chlorpromazine (CPZ) therapy presents with a recurrence of auditory hallucinations. Which medication would be the most appropriate next choice?

A. Haloperidol
B. Clozapine (Correct Answer)
C. Sulpiride
D. Tianeptin

Explanation: ### Explanation **Correct Answer: B. Clozapine** **Why it is correct:** The patient is experiencing a recurrence of symptoms (auditory hallucinations) while on Chlorpromazine, a typical antipsychotic. This indicates **Treatment-Resistant Schizophrenia (TRS)**. Clinically, TRS is defined as a failure of at least two adequate trials of antipsychotic medications (at least one being a second-generation antipsychotic, though failure of a potent typical antipsychotic also qualifies). **Clozapine** is the "gold standard" and the drug of choice for treatment-resistant schizophrenia. It is the only antipsychotic proven to be effective in patients who do not respond to standard dopamine-D2 receptor antagonists. **Why the other options are incorrect:** * **A. Haloperidol:** This is a high-potency typical antipsychotic. If a patient fails on one typical antipsychotic (Chlorpromazine), switching to another typical antipsychotic (Haloperidol) is unlikely to provide significant benefit in resistant cases and increases the risk of Extrapyramidal Side Effects (EPS). * **C. Sulpiride:** This is an atypical antipsychotic (substituted benzamide) primarily acting on D2/D3 receptors. While it has a lower EPS profile, it is not the preferred choice for treatment resistance compared to Clozapine. * **D. Tianeptine:** This is an antidepressant (selective serotonin reuptake enhancer - SSRE). It has no role in treating the primary psychotic symptoms of schizophrenia. **High-Yield Clinical Pearls for NEET-PG:** * **Clozapine Monitoring:** The most serious side effect is **agranulocytosis** (1%). Absolute Neutrophil Count (ANC) must be monitored weekly for the first 6 months. * **Other Side Effects:** Clozapine is associated with the highest risk of **seizures** (dose-dependent), **sialorrhea** (excessive drooling), and **metabolic syndrome**, but it has the **lowest risk of EPS** and Tardive Dyskinesia. * **Indication:** Clozapine is also the drug of choice for schizophrenia associated with persistent **suicidality**.

Question 237: Which drug is known to cause agranulocytosis?

A. Pimozide
B. Clozapine (Correct Answer)
C. Risperidone
D. Olanzapine

Explanation: **Explanation:** **Clozapine** is an atypical (second-generation) antipsychotic reserved for treatment-resistant schizophrenia. Its most serious and life-threatening side effect is **agranulocytosis** (a severe decrease in the absolute neutrophil count <500/mm³), which occurs in approximately 0.8–1% of patients. The mechanism is thought to be an immune-mediated destruction of granulocytes. Due to this risk, mandatory hematological monitoring (ANC levels) is required—weekly for the first 6 months, biweekly for the next 6 months, and monthly thereafter. **Analysis of Incorrect Options:** * **A. Pimozide:** A typical antipsychotic primarily used for Tourette’s disorder. Its main concern is QT interval prolongation and sudden cardiac death, not agranulocytosis. * **C. Risperidone:** An atypical antipsychotic known for causing significant hyperprolactinemia and extrapyramidal symptoms (EPS) at higher doses, but it does not carry a significant risk of bone marrow suppression. * **D. Olanzapine:** Structurally similar to clozapine but lacks the significant risk of agranulocytosis. Its primary side effects are significant weight gain, sedation, and metabolic syndrome. **High-Yield Clinical Pearls for NEET-PG:** * **Clozapine** is the only antipsychotic proven to reduce **suicidal behavior** in schizophrenia. * **Seizures** are a dose-dependent side effect of Clozapine (highest risk at doses >600mg). * **Sialorrhea** (excessive salivation) is a paradoxical but common side effect. * **Myocarditis** is another rare but fatal complication of Clozapine, usually occurring within the first month of treatment.

Question 238: Clozapine therapy should be stopped when the WBC count falls lower than what value?

A. 3000 / mm3 (Correct Answer)
B. 1500 / mm3
C. 2000 / mm3
D. 1000 / mm3

Explanation: **Explanation:** Clozapine is an atypical antipsychotic reserved for treatment-resistant schizophrenia. Its most serious side effect is **agranulocytosis** (a life-threatening drop in white blood cell count), which occurs in approximately 0.8–1% of patients. To mitigate this risk, strict hematological monitoring is mandatory. **Why Option A is correct:** According to standard clinical guidelines (and frequently tested NEET-PG protocols), Clozapine therapy must be **immediately interrupted** if the **Total Leukocyte Count (WBC) falls below 3000/mm³** or if the **Absolute Neutrophil Count (ANC) falls below 1500/mm³**. This threshold acts as a safety buffer to prevent progression to severe agranulocytosis. **Analysis of Incorrect Options:** * **Option B (1500 / mm³):** This is the threshold for the **ANC (Absolute Neutrophil Count)**, not the total WBC count. Confusing WBC and ANC values is a common examiner trap. * **Option C (2000 / mm³):** While this indicates moderate leukopenia, the protocol mandates stopping the drug earlier (at 3000) to ensure patient safety. * **Option D (1000 / mm³):** An ANC below 500–1000/mm³ is defined as severe agranulocytosis. Waiting for the count to reach this level before stopping the drug would put the patient at extreme risk of fatal sepsis. **High-Yield Clinical Pearls for NEET-PG:** * **Monitoring Schedule:** Weekly for the first 6 months, every 2 weeks for the next 6 months, and monthly thereafter. * **Other Side Effects:** Sialorrhea (hypersalivation), sedation, weight gain, and lowering of the seizure threshold (dose-dependent). * **Drug of Choice:** Clozapine is the gold standard for **treatment-resistant schizophrenia** and for reducing **suicidal behavior** in schizophrenic patients. * **Note:** Clozapine is the only antipsychotic that does *not* cause Tardive Dyskinesia and has minimal Extrapyramidal Side Effects (EPS).

Question 239: A 30-year-old man with schizophrenia has been very withdrawn and apathetic for more than 10 years. He is currently taking an antipsychotic agent that is helping him to be more outgoing and sociable. However, the patient is experiencing seizures and agranulocytosis. Which antipsychotic agent is this patient most likely to be taking?

A. risperidone
B. thioridazine
C. olanzapine
D. clozapine (Correct Answer)

Explanation: **Explanation:** The patient is most likely taking **Clozapine**, which is the "gold standard" for treatment-resistant schizophrenia. **Why Clozapine is the Correct Answer:** 1. **Efficacy on Negative Symptoms:** The patient has been "withdrawn and apathetic" (negative symptoms) for 10 years. Clozapine is highly effective in improving social withdrawal and treatment-refractory cases where other antipsychotics have failed. 2. **Agranulocytosis:** This is the most characteristic and life-threatening side effect of Clozapine (occurring in ~1% of patients). It necessitates mandatory weekly WBC monitoring for the first six months. 3. **Seizures:** Clozapine significantly lowers the seizure threshold in a dose-dependent manner. **Why Other Options are Incorrect:** * **Risperidone (A):** An atypical antipsychotic commonly causing hyperprolactinemia and extrapyramidal symptoms (EPS) at higher doses, but not typically associated with agranulocytosis. * **Thioridazine (B):** A typical antipsychotic known for causing pigmentary retinopathy and QTc prolongation. While it can lower the seizure threshold, it does not cause agranulocytosis. * **Olanzapine (C):** Closely related to clozapine but lacks the risk of agranulocytosis. Its primary side effects are significant weight gain and metabolic syndrome. **NEET-PG High-Yield Pearls:** * **Clozapine** is the only antipsychotic proven to reduce **suicidal behavior** in schizophrenia. * **Side Effect Profile:** Sialorrhea (excessive salivation), weight gain, myocarditis, and constipation (can lead to paralytic ileus). * **Monitoring:** Absolute Neutrophil Count (ANC) must be >1500/mm³ to initiate therapy. * It has the **least potential** for causing Extrapyramidal Symptoms (EPS) and Tardive Dyskinesia.

Question 240: Which of the following is an example of an atypical antipsychotic?

A. Olanzapine (Correct Answer)
B. Haloperidol
C. Amitriptyline
D. Zuclopenthixol

Explanation: **Explanation:** **Correct Answer: A. Olanzapine** Olanzapine is a Second-Generation Antipsychotic (SGA), also known as an **atypical antipsychotic**. Unlike typical antipsychotics that primarily block D2 receptors, atypical agents like Olanzapine act as **Serotonin-Dopamine Antagonists (SDAs)**. They block both 5-HT2A and D2 receptors. This dual mechanism provides efficacy against both positive and negative symptoms of schizophrenia and significantly reduces the risk of Extrapyramidal Side Effects (EPS). **Analysis of Incorrect Options:** * **B. Haloperidol:** A potent First-Generation Antipsychotic (FGA) or "typical" antipsychotic. It is a high-potency D2 receptor antagonist known for a high incidence of EPS and hyperprolactinemia. * **C. Amitriptyline:** A Tricyclic Antidepressant (TCA). It inhibits the reuptake of Serotonin and Norepinephrine and is used for depression and neuropathic pain, not as an antipsychotic. * **D. Zuclopenthixol:** A typical antipsychotic belonging to the Thioxanthene class. It is often used in long-acting injectable (depot) forms for acute psychosis or maintenance therapy. **High-Yield Clinical Pearls for NEET-PG:** * **Metabolic Profile:** Olanzapine is associated with significant **weight gain**, hyperglycemia, and dyslipidemia (highest risk among SGAs along with Clozapine). * **Clozapine:** The first atypical antipsychotic and the "Gold Standard" for **treatment-resistant schizophrenia**. It requires monitoring for agranulocytosis. * **Aripiprazole:** A unique atypical antipsychotic that acts as a **D2 partial agonist**. * **Side Effect Rule:** Typical antipsychotics = High EPS risk; Atypical antipsychotics = High Metabolic risk.

Practice by Chapter

Principles of Psychopharmacology

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Antipsychotic Medications

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Antidepressant Medications

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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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