Drugs in Psychiatric Disorders — MCQs

Drugs in Psychiatric Disorders Indian Medical PG Practice Questions and MCQs

Question 351: Antipsychotic drug with the least extrapyramidal symptoms?

A. Pimozide
B. Clozapine (Correct Answer)
C. Fluphenazine
D. Thioridazine

Explanation: ***Clozapine***- **Atypical antipsychotics** like clozapine have a **lower affinity for D2 dopamine receptors** and a higher affinity for serotonin 5-HT2A receptors, which contributes to their reduced risk of EPS.- It is known for its effectiveness in **treatment-resistant schizophrenia** and its **low propensity for causing movement disorders** [1, 2].*Pimozide*- **Pimozide** is a **typical antipsychotic** (first-generation) that has a high affinity for D2 dopamine receptors.- This strong D2 antagonism leads to a **higher risk of extrapyramidal symptoms**.*Thioridazine*- **Thioridazine** is a **low-potency typical antipsychotic** that, while having a lower incidence of EPS compared to high-potency typicals, still carries a significant risk [1].- It is associated with other side effects such as **cardiac conduction abnormalities** (e.g., QT prolongation) at higher doses.*Fluphenazine*- **Fluphenazine** is a **high-potency typical antipsychotic** with strong D2 receptor antagonism.- High-potency typical antipsychotics like **Fluphenazine** are known for their **high risk of extrapyramidal symptoms** [1].

Question 352: Which drug is used for long-term maintenance in opioid addiction?

A. Naloxone
B. Nalorphine
C. Methadone (Correct Answer)
D. Butorphanol

Explanation: ***Methadone*** - **Methadone** is a long-acting opioid agonist used daily for **maintenance therapy** in opioid addiction, preventing withdrawal symptoms and reducing cravings. - Its long half-life allows for once-daily dosing, which helps in stabilizing patients and reducing illicit opioid use. - Along with **buprenorphine** (a partial agonist), methadone is one of the two primary medications used for opioid maintenance therapy. *Naloxone* - **Naloxone** is an **opioid antagonist** used to rapidly reverse opioid overdose by competitively binding to opioid receptors. - It is not used for long-term maintenance but rather as an emergency intervention to counteract life-threatening respiratory depression. *Nalorphine* - **Nalorphine** is an older, mixed opioid agonist-antagonist that was once used for opioid overdose but has largely been replaced by naloxone due to its own opioid agonistic effects. - It does not have a role in current long-term maintenance treatment for opioid addiction. *Butorphanol* - **Butorphanol** is a mixed opioid agonist-antagonist primarily used as an analgesic, particularly for pain management. - It can precipitate withdrawal in opioid-dependent individuals and is not indicated for the treatment or maintenance of opioid addiction.

Question 353: Which of the following is a typical antipsychotic drug?

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

Explanation: ***Haloperidol*** - **Haloperidol** is a **first-generation (typical)** antipsychotic that primarily blocks **D2 dopamine receptors** in the brain. - It is often used for acute psychotic episodes and has a higher risk of **extrapyramidal symptoms (EPS)** compared to atypical antipsychotics. *Clozapine* - **Clozapine** is an **atypical (second-generation)** antipsychotic, known for its effectiveness in **treatment-resistant schizophrenia**. - Its mechanism involves broader receptor binding, including **dopamine** and **serotonin** receptors, and it carries risks like **agranulocytosis** and **myocarditis**. *Risperidone* - **Risperidone** is an **atypical (second-generation)** antipsychotic, known for its mixed **D2 dopamine** and **5-HT2A serotonin** receptor antagonism. - It has a lower risk of EPS than typical antipsychotics but can cause dose-dependent **hyperprolactinemia**. *Olanzapine* - **Olanzapine** is an **atypical (second-generation)** antipsychotic with broad receptor binding, including **dopamine, serotonin, histamine, and muscarinic receptors**. - It is associated with a significant risk of **metabolic side effects**, such as weight gain, hyperglycemia, and dyslipidemia.

Question 354: Which of the following drugs is given for detoxification of alcohol in chronic alcoholics?

A. Haloperidol
B. Naltrexone
C. Chlordiazepoxide (Correct Answer)
D. Buprenorphine

Explanation: ***Correct Option: Chlordiazepoxide*** - **Chlordiazepoxide** is a **benzodiazepine** commonly used for acute alcohol withdrawal syndrome due to its long half-life and efficacy in reducing withdrawal symptoms. - It helps prevent **seizures** and **delirium tremens** by acting on GABA receptors, reducing neuronal hyperexcitability. *Incorrect Option: Haloperidol* - **Haloperidol** is an **antipsychotic** medication primarily used to manage acute psychosis, agitation, or delirium. - It does not directly address alcohol withdrawal symptoms and can potentially lower the **seizure threshold**, which is risky in alcohol withdrawal. *Incorrect Option: Naltrexone* - **Naltrexone** is an **opioid antagonist** used to reduce alcohol cravings and prevent relapse in individuals who have achieved abstinence. - It is not used for acute detoxification or withdrawal management, as it does not alleviate acute symptoms. *Incorrect Option: Buprenorphine* - **Buprenorphine** is a **partial opioid agonist** used primarily in the treatment of opioid use disorder. - It has no role in the detoxification or management of alcohol withdrawal syndrome.

Question 355: Sedation as an adverse effect is most commonly associated with which of the following atypical antipsychotics?

A. Risperidone
B. Olanzapine
C. Quetiapine (Correct Answer)
D. Aripiprazole

Explanation: ***Quetiapine*** - **Quetiapine** is known for its strong **H1 histamine receptor blockade**, which directly contributes to its prominent sedating effects. - This sedation is often dose-dependent and can be beneficial for patients with insomnia or agitation, but it is also a common complaint and reason for discontinuation. - Among the options listed, quetiapine is classically taught as the **most sedating** atypical antipsychotic. *Risperidone* - While risperidone can cause some sedation [1], it is generally less sedating than quetiapine or olanzapine and is more commonly associated with **extrapyramidal symptoms (EPS)**, especially at higher doses [1]. - Its mechanism of action primarily involves **D2 dopamine receptor blockade** and **5-HT2A serotonin receptor blockade** [1]. *Olanzapine* - **Olanzapine** also causes significant sedation [1] due to its strong antagonism of **H1 histamine receptors** and **alpha-1 adrenergic receptors**. - Clinically, olanzapine's sedative effects are comparable to quetiapine, though quetiapine is traditionally emphasized in exam contexts as the most sedating among these options. - Olanzapine is additionally notable for significant **metabolic side effects** like weight gain and dyslipidemia. *Aripiprazole* - **Aripiprazole** acts as a **partial agonist** at D2 dopamine receptors and 5-HT1A serotonin receptors, and an antagonist at 5-HT2A serotonin receptors, which results in minimal sedation. - It is often considered to be more **activating** or have a **neutral** effect on sedation compared to other atypical antipsychotics.

Question 356: Which of the antidepressants is used in low doses as a hypnotic?

A. fluoxetine
B. fluvoxamine
C. bupropion
D. trazodone (Correct Answer)

Explanation: ***trazodone*** - **Trazodone** is an antidepressant that is frequently prescribed off-label at low doses as a **hypnotic** due to its potent **histamine H1 receptor antagonism** and **alpha-1 adrenergic blocking effects**, inducing sedation. - Its sedative properties differentiate it from other antidepressants that are primarily stimulating. *fluoxetine* - **Fluoxetine** is a **selective serotonin reuptake inhibitor (SSRI)** known for its **activating** effects, making it a poor choice for a hypnotic. - It is more likely to cause **insomnia** and agitation rather than sedation. *fluvoxamine* - **Fluvoxamine** is another **SSRI** primarily used for **obsessive-compulsive disorder (OCD)**. - Like other SSRIs, its primary action is not sedation, and it can sometimes lead to **sleep disturbances**. *bupropion* - **Bupropion** is a **norepinephrine-dopamine reuptake inhibitor (NDRI)** known for its **stimulating effects** and lack of sexual side effects. - It is often avoided in patients with **insomnia** due to its activating properties and is not used as a hypnotic.

Question 357: Antipsychotic drug causing retinal pigment disorder is which?

A. Clozapine
B. Chlorpromazine
C. None of the options
D. Thioridazine (Correct Answer)

Explanation: ***Thioridazine*** - **Thioridazine** is a **first-generation antipsychotic** known to cause **retinal pigmentary changes** (pigmentary retinopathy) at high doses, particularly above 800 mg/day. - This condition can lead to **vision loss** due to the deposition of melanin-like pigment in the retina and progressive retinal degeneration. - This is a dose-related toxic effect and is one of the reasons thioridazine is less commonly used today. *Clozapine* - **Clozapine** is primarily associated with severe side effects like **agranulocytosis** and **myocarditis**. - It is not typically known to cause **retinal pigment disorder** as a common or significant side effect. *Chlorpromazine* - **Chlorpromazine**, another first-generation antipsychotic, is more commonly linked to **corneal and lenticular opacities** (blue-gray discoloration of the eye) than retinal pigment changes. - While it can affect the eye, its primary ocular toxicity differs from the **retinal pigment disorder** caused by thioridazine. *None of the options* - This option is incorrect because **Thioridazine** is a well-established cause of **retinal pigment disorder**. - There is a specific antipsychotic drug listed that causes this condition.

Question 358: What is a common side effect of a selective serotonin reuptake inhibitor (SSRI) medication prescribed to a 50-year-old woman with depression?

A. Hepatotoxicity
B. Weight gain
C. Hypertension
D. Decreased libido and difficulty achieving orgasm (Correct Answer)

Explanation: ***Decreased libido and difficulty achieving orgasm*** - **Sexual dysfunction**, including decreased libido, anorgasmia, and ejaculatory delay, is a very common and often dose-dependent side effect of SSRIs. - This is attributed to increased serotonin levels affecting **dopamine** and **norepinephrine** pathways involved in sexual response. *Hepatotoxicity* - While possible with many medications, **severe hepatotoxicity** is rare with SSRIs and not considered a common side effect in routine clinical practice. - Liver enzyme elevations can occur, but significant liver damage requiring discontinuation is infrequent. *Weight gain* - **Weight gain** is a known side effect of some antidepressants, particularly **tricyclic antidepressants (TCAs)** and some **atypical antipsychotics**, but it is less consistently associated with SSRIs. - Although some SSRIs can cause weight gain, it is not as universally common or as prominent as sexual dysfunction. *Hypertension* - **Hypertension** is not a common side effect of SSRIs; in fact, some studies suggest a potential for SSRIs to slightly lower **blood pressure**. - **Serotonin-norepinephrine reuptake inhibitors (SNRIs)**, like venlafaxine, are more likely to cause dose-dependent increases in blood pressure.

Practice by Chapter

Antipsychotics: Typical and Atypical

Practice Questions

Antidepressants: SSRIs and SNRIs

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Tricyclic Antidepressants

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MAO Inhibitors

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Mood Stabilizers

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Anxiolytics

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Drugs for ADHD

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Drugs for Sleep Disorders

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Drugs for Dementia

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Drug-Induced Psychiatric Symptoms

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