Substance Use Disorders — MCQs

Substance Use Disorders Indian Medical PG Practice Questions and MCQs

Question 161: What is the loading dose of diazepam for alcohol withdrawal?

A. 80 mg
B. 50 mg
C. 40 mg
D. 20 mg (Correct Answer)

Explanation: **Explanation:** The management of alcohol withdrawal syndrome (AWS) primarily involves the use of benzodiazepines (BZDs) to prevent complications like seizures and delirium tremens. **Diazepam** is a long-acting BZD preferred for its rapid onset and self-tapering effect due to its long half-life. **Why 20 mg is correct:** In the **symptom-triggered loading dose strategy**, the goal is to achieve rapid sedation. The standard protocol involves administering **10–20 mg of diazepam** orally every 1 to 2 hours until the patient is adequately sedated (measured by a CIWA-Ar score < 10). A dose of **20 mg** is the established upper limit for a single loading dose to safely initiate this process without causing immediate respiratory depression. **Analysis of Incorrect Options:** * **Options A (80 mg) and B (50 mg):** These doses are excessively high for a single loading dose and pose a significant risk of over-sedation, respiratory failure, and coma. * **Option C (40 mg):** While some severe cases may eventually require high cumulative doses, 40 mg as an initial loading dose exceeds standard safety guidelines for starting therapy. **High-Yield Clinical Pearls for NEET-PG:** * **Drug of Choice:** Benzodiazepines (Diazepam or Chlordiazepoxide) are the gold standard for AWS. * **Liver Impairment:** In patients with cirrhosis or elderly patients, use **LOT** (Lorazepam, Oxazepam, Temazepam) as they do not have active metabolites and are not dependent on hepatic oxidation. * **Wernicke’s Encephalopathy:** Always administer **Thiamine** before Glucose to prevent precipitating Wernicke’s. * **Delirium Tremens:** Occurs 48–96 hours after the last drink; characterized by clouding of consciousness and autonomic instability.

Question 162: All of the following are criteria for substance dependence except?

A. Tolerance
B. Withdrawal symptoms
C. Inability to quit the drug
D. Use of illegal substances (Correct Answer)

Explanation: The diagnosis of **Substance Dependence** is based on a cluster of physiological, behavioral, and cognitive phenomena. According to the **ICD-10** (which is high-yield for NEET-PG), a diagnosis requires 3 or more of 6 specific criteria occurring together at some time during the previous year. ### Why "Use of illegal substances" is the Correct Answer: The legal status of a substance is **not** a diagnostic criterion for dependence. Dependence is a clinical and biological phenomenon. One can be severely dependent on legal substances (e.g., Alcohol, Tobacco, or prescription Benzodiazepines) or may use illegal substances (e.g., recreational Cannabis) without meeting the clinical threshold for dependence. ### Explanation of Incorrect Options (Criteria for Dependence): * **Tolerance (Option A):** A need for significantly increased amounts of the substance to achieve intoxication or the desired effect. * **Withdrawal symptoms (Option B):** A characteristic withdrawal syndrome for the substance or using the same (or closely related) substance to relieve or avoid withdrawal symptoms. * **Inability to quit the drug (Option C):** This refers to a persistent desire or unsuccessful efforts to cut down or control substance use (loss of control). ### NEET-PG High-Yield Clinical Pearls: * **ICD-10 Criteria for Dependence (The "6 Pillars"):** 1. Strong desire/compulsion to take the substance (**Craving**). 2. Difficulties in controlling use (**Impaired Control**). 3. Physiological **Withdrawal** state. 4. Evidence of **Tolerance**. 5. Progressive **Neglect** of alternative pleasures or interests. 6. Persisting with use despite clear evidence of **Harmful Consequences**. * **DSM-5 Update:** Note that DSM-5 has replaced the categories of "Abuse" and "Dependence" with a single spectrum called **Substance Use Disorder (SUD)**, graded by severity based on the number of symptoms present.

Question 163: Which defence mechanism is commonly shown by drug addicts?

A. Transformation
B. Projection
C. Repetition
D. Denial (Correct Answer)

Explanation: **Explanation:** In psychiatry, **Denial** is the most characteristic and frequently used defense mechanism in individuals with Substance Use Disorders (SUD). **1. Why Denial is Correct:** Denial is a primitive (narcissistic) defense mechanism where the individual refuses to acknowledge some painful aspect of external reality or subjective experience that is apparent to others. In drug addiction, the patient ignores the severity of their dependency, the negative consequences on their health/relationships, or even the existence of the addiction itself (e.g., "I can quit whenever I want" or "I only use it to relax"). It serves as a psychological barrier that prevents the patient from seeking treatment. **2. Analysis of Incorrect Options:** * **Transformation:** This is not a standard psychiatric defense mechanism. It is often confused with *Sublimation* (transforming unacceptable impulses into socially acceptable actions) or *Conversion* (transforming psychological conflict into physical symptoms). * **Projection:** While addicts may occasionally use projection (attributing their own unacceptable urges to others, e.g., "My wife is the one with the temper problem"), it is not the primary or most common defense associated with the core of addiction. * **Repetition:** This refers to "Repetition Compulsion," a psychological phenomenon where a person repeats a traumatic event or its circumstances over and over. It is not classified as a primary defense mechanism for substance use. **Clinical Pearls for NEET-PG:** * **Rationalization** is the second most common defense in addiction (providing logical but false reasons for drug use, e.g., "I use because my job is stressful"). * **The "CAGE" Questionnaire** is a high-yield screening tool for alcohol dependence; the "E" stands for "Eye-opener." * **Stages of Change (Proshaska and DiClemente):** Denial is most prominent in the **Pre-contemplation stage**, where the patient has no intention of changing behavior.

Question 164: What is the incidence of suicide?

A. 8-10 per 100 population
B. 8-10 per 10,000 population
C. 8-10 per 100,000 population (Correct Answer)
D. 8-10 per 1 billion population

Explanation: **Explanation:** The incidence of suicide is a critical epidemiological metric in psychiatry. Globally, and historically in the Indian context, the suicide rate is measured as the number of completed suicides per **100,000 population per year**. 1. **Why Option C is Correct:** According to the World Health Organization (WHO) and the National Crime Records Bureau (NCRB) of India, the average suicide rate typically fluctuates between **8–12 per 100,000 population**. While recent Indian data shows a slight upward trend (approx. 12 per 100,000), "8–10 per 100,000" remains the standard textbook figure for exams. 2. **Why Other Options are Incorrect:** * **Option A (per 100):** This would imply a 10% mortality rate due to suicide in the general population, which is statistically impossible. * **Option B (per 10,000):** This overestimates the incidence by tenfold. * **Option D (per 1 billion):** This is an extreme underestimate; suicide is a leading cause of death globally, not a rare event occurring only a few times per billion people. **High-Yield Clinical Pearls for NEET-PG:** * **Most Common Method:** In India, **hanging** is the most common method of suicide, followed by poisoning (pesticides). * **Gender Paradox:** Suicide **attempts** are more common in **females**, but **completed suicides** are more common in **males** (due to the use of more lethal methods). * **Risk Factors:** The single strongest predictor of suicide is a **previous suicide attempt**. * **Psychiatric Comorbidity:** Over 90% of individuals who die by suicide have a diagnosable mental disorder, most commonly **Depression** or **Substance Use Disorders**. * **Age Group:** The highest rates are often seen in the young adult (15–39 years) and elderly populations.

Question 165: A child presents with sweating, yawning, lacrimation, and tachycardia. What is the likely diagnosis?

A. Heroin withdrawal (Correct Answer)
B. Cocaine withdrawal
C. LSD withdrawal
D. Marijuana withdrawal

Explanation: The clinical presentation of **sweating, yawning, lacrimation, and tachycardia** is a classic "high-yield" constellation of symptoms indicating **Opioid (Heroin) withdrawal**. ### 1. Why Heroin Withdrawal is Correct Opioids are CNS depressants that cause miosis (pinpoint pupils), constipation, and bradycardia. When the drug is withdrawn, the body experiences a "rebound" of the sympathetic nervous system. * **Early signs:** Yawning, lacrimation (tearing), rhinorrhea (runny nose), and diaphoresis (sweating). * **Later signs:** Mydriasis (dilated pupils), tachycardia, piloerection ("goosebumps" – the origin of the term "cold turkey"), and abdominal cramps/diarrhea. * **Key Concept:** While distressing, opioid withdrawal is generally **not life-threatening** (unlike alcohol or benzodiazepine withdrawal). ### 2. Why Other Options are Incorrect * **Cocaine Withdrawal:** Presents with "the crash"—dysphoria, intense craving, hypersomnia (excessive sleep), and hyperphagia (increased appetite). It does not typically cause lacrimation or yawning. * **LSD Withdrawal:** LSD does not produce a significant physical withdrawal syndrome; its effects are primarily psychological (flashbacks). * **Marijuana Withdrawal:** Symptoms are mild and non-specific, including irritability, insomnia, and decreased appetite, but lack the autonomic hyperactivity seen here. ### 3. NEET-PG Clinical Pearls * **Antidote for Acute Opioid Overdose:** Naloxone (short-acting Opioid Antagonist). * **Treatment for Opioid Withdrawal:** Methadone or Buprenorphine (Substitution therapy); Clonidine can be used to manage autonomic symptoms like tachycardia. * **The "Piloerection" Fact:** Piloerection is a pathognomonic sign of severe opioid withdrawal. * **Pupillary Sign:** Remember: **O**pioid **O**verdose = Pinpoint pupils; **O**pioid **W**ithdrawal = Dilated pupils.

Question 166: A person develops episodes of rage after using a certain drug, during which they run about and indiscriminately injure anyone encountered. What substance is this person likely addicted to?

A. Alcohol
B. Cannabis (Correct Answer)
C. Opium
D. Cocaine

Explanation: **Explanation:** The clinical scenario describes a phenomenon known as **"Running Amok,"** which is a culture-bound syndrome traditionally associated with chronic **Cannabis** use (though it can also occur in other psychiatric conditions). It is characterized by a period of brooding followed by a sudden, violent outburst where the individual runs about and indiscriminately attacks people or objects. **Why Cannabis is correct:** Chronic cannabis use can lead to various psychiatric manifestations, including "Cannabis Psychosis" and "Amok." In this state, the individual experiences extreme rage and loss of impulse control. Other cannabis-related psychiatric terms high-yield for exams include **"Flashbacks"** and **"Amotivational Syndrome"** (characterized by apathy and lack of ambition). **Why other options are incorrect:** * **Alcohol:** While alcohol causes disinhibition and aggression (Pathological Intoxication), the specific pattern of "running about and indiscriminately injuring" is the classic description of Amok linked to cannabis in psychiatric literature. * **Opium:** Opioids are central nervous system depressants. Toxicity typically presents with sedation, pinpoint pupils, and respiratory depression, rather than violent rage. * **Cocaine:** Cocaine is a sympathomimetic that causes euphoria, paranoia, and "formication" (Cocaine bugs/Magnan’s sign). While it can cause agitation, it is not the primary substance associated with the "Amok" description. **High-Yield Clinical Pearls for NEET-PG:** * **Amok:** Sudden mass assault followed by amnesia for the event. * **Run Amok vs. Berserk:** Both involve violent rage; "Amok" is the term most frequently tested in the context of Cannabis. * **Active Principle:** Delta-9-tetrahydrocannabinol (THC). * **Receptor:** CB1 (CNS) and CB2 (Periphery).

Question 167: At what dose of alcohol intoxication are alcoholic blackouts typically observed?

A. 20-30 mg/dl
B. 30-80 mg/dl
C. 80-200 mg/dl
D. 200-300 mg/dl (Correct Answer)

Explanation: **Explanation:** **Alcoholic blackouts** are episodes of anterograde amnesia where an individual remains conscious and functional but cannot form new long-term memories. This occurs due to the acute inhibition of the **hippocampus**, specifically interfering with long-term potentiation (LTP). **Why Option D is Correct:** Blackouts typically occur when Blood Alcohol Concentration (BAC) rises rapidly, usually reaching levels of **200–300 mg/dl**. At this high concentration, the neurochemical disruption in the brain is severe enough to "switch off" the recording of memories while sparing basic motor functions and consciousness. **Analysis of Incorrect Options:** * **A (20-30 mg/dl):** This is a very low level. At this stage, an individual might experience mild relaxation or slight changes in mood, but cognitive functions remain intact. * **B (30-80 mg/dl):** This level causes mild impairment in coordination and reaction time. In many countries, 80 mg/dl is the legal limit for driving. * **C (80-200 mg/dl):** This range is associated with significant intoxication, slurred speech, and ataxia (drunkenness), but it is generally below the threshold for complete memory "blackouts." **High-Yield Clinical Pearls for NEET-PG:** * **Mechanism:** Alcohol antagonizes **NMDA receptors** and enhances **GABA receptors** in the hippocampus, blocking memory consolidation. * **Types of Blackouts:** 1. **En bloc:** Total permanent amnesia for a period. 2. **Fragmentary (Brownouts):** Partial memory loss where cues can help recall. * **Lethal Dose:** Respiratory depression and death typically occur at BAC levels >400–500 mg/dl. * **Wernicke-Korsakoff Syndrome:** While blackouts are acute, chronic memory loss in alcoholics is due to Thiamine (B1) deficiency.

Question 168: Nicotine replacement therapy is available in all forms except which of the following?

A. Chewing gum
B. Lozenges
C. Patch
D. Tablets (Correct Answer)

Explanation: **Explanation:** Nicotine Replacement Therapy (NRT) is designed to deliver nicotine to the systemic circulation to reduce withdrawal symptoms without the harmful toxins found in tobacco smoke. The key pharmacological principle of NRT is **transmucosal or transdermal absorption**, which avoids the **extensive first-pass metabolism** in the liver. **Why "Tablets" is the correct answer:** Nicotine is not administered as an oral tablet (to be swallowed) because it has poor oral bioavailability. When swallowed, nicotine is absorbed into the portal circulation and rapidly metabolized by the liver, making it ineffective. While "sublingual tablets" exist in some global markets (placed under the tongue for mucosal absorption), standard oral tablets are not a recognized form of NRT. **Analysis of Incorrect Options:** * **A. Chewing gum:** One of the most common forms (available in 2mg and 4mg). Nicotine is absorbed through the buccal mucosa. * **B. Lozenges:** These are dissolved slowly in the mouth, allowing for transmucosal absorption. * **C. Patch:** A transdermal delivery system that provides a steady, controlled release of nicotine over 16 or 24 hours, maintaining stable plasma levels. **Clinical Pearls for NEET-PG:** * **Other NRT forms:** Nasal sprays and inhalers (not mentioned in options but clinically used). * **Non-Nicotine Pharmacotherapy:** * **Varenicline:** A partial agonist at the $\alpha4\beta2$ nicotinic acetylcholine receptor (Most effective single agent). * **Bupropion:** An atypical antidepressant (NDRI) that reduces cravings. * **Contraindication:** NRT should be used with caution in patients with recent myocardial infarction (within 2 weeks) or unstable angina.

Question 169: What is the recommended pharmacological treatment for alcohol dependence?

A. Morphine
B. Chlordiazepoxide (Correct Answer)
C. Sertraline
D. Methadone

Explanation: **Explanation:** The management of alcohol dependence involves two phases: detoxification (treating withdrawal) and maintenance (preventing relapse). In the acute phase, **Chlordiazepoxide** is the drug of choice. **Why Chlordiazepoxide is correct:** Alcohol is a CNS depressant that enhances GABAergic tone. Chronic use leads to downregulation of GABA receptors. Abrupt cessation causes a hyperexcitable state (withdrawal). Chlordiazepoxide is a long-acting **Benzodiazepine (BZD)** that shows **cross-tolerance** with alcohol. It substitutes for alcohol’s effect on GABA receptors, preventing seizures and delirium tremens. Its long half-life ensures a "smooth" taper, reducing the risk of rebound symptoms. **Analysis of Incorrect Options:** * **A. Morphine:** An opioid agonist used for pain management. It has no role in alcohol withdrawal and carries a high risk of respiratory depression and addiction. * **C. Sertraline:** An SSRI used for depression or anxiety. While it may treat comorbid depression in a recovering alcoholic, it does not treat the primary withdrawal syndrome. * **D. Methadone:** A long-acting opioid agonist used specifically for **Opioid Use Disorder** (detoxification and maintenance), not alcohol dependence. **High-Yield NEET-PG Pearls:** * **Drug of Choice (DOC) for Alcohol Withdrawal:** Benzodiazepines (Chlordiazepoxide or Diazepam). * **Liver Impairment:** If the patient has cirrhosis or liver failure, use **LOT** (Lorazepam, Oxazepam, Temazepam) as they undergo extrahepatic metabolism. * **Relapse Prevention (FDA Approved):** Disulfiram (Aversion therapy), Acamprosate (reduces cravings), and Naltrexone (reduces the "high"). * **Wernicke’s Encephalopathy:** Always administer **Thiamine (B1)** before glucose to prevent precipitating acute neurological symptoms.

Question 170: All of the following are seen in nicotine withdrawal except?

A. Hyperhidrosis (Correct Answer)
B. Anxiety
C. Bradycardia
D. Insomnia

Explanation: **Explanation:** Nicotine is a potent stimulant that acts on nicotinic acetylcholine receptors, leading to the release of dopamine, norepinephrine, and acetylcholine. When a chronic user stops smoking, the central nervous system undergoes a "rebound" effect. **Why Hyperhidrosis is the correct answer:** Hyperhidrosis (excessive sweating) is a sign of **sympathetic overactivity**, which is characteristic of withdrawal from CNS depressants like alcohol or opioids. In contrast, nicotine withdrawal is primarily characterized by irritability, decreased heart rate, and increased appetite. Hyperhidrosis is **not** a diagnostic criterion for nicotine withdrawal according to the DSM-5 or ICD-11. **Analysis of incorrect options:** * **Anxiety (B):** This is one of the most common psychological symptoms of nicotine withdrawal, often accompanied by irritability, frustration, and restlessness. * **Bradycardia (C):** Nicotine is a stimulant that increases heart rate. Upon cessation, there is a physiological "crash," leading to a **decrease in heart rate** (bradycardia). This is a high-yield distinction from most other withdrawal syndromes. * **Insomnia (D):** Sleep disturbances, including difficulty falling asleep and fragmented sleep, are classic features of the withdrawal syndrome. **Clinical Pearls for NEET-PG:** * **Weight Gain:** Nicotine withdrawal typically causes increased appetite and weight gain (due to decreased metabolic rate and oral substitution). * **Timeline:** Symptoms peak within 24–48 hours and usually subside within 3–4 weeks. * **First-line Treatment:** Nicotine Replacement Therapy (NRT), Varenicline (partial agonist), and Bupropion (atypical antidepressant). * **Key Distinguisher:** Unlike alcohol or opioid withdrawal, nicotine withdrawal is **not** life-threatening.

Practice by Chapter

Neurobiology of Addiction

Practice Questions

Alcohol Use Disorder

Practice Questions

Opioid Use Disorder

Practice Questions

Cannabis Use Disorder

Practice Questions

Stimulant Use Disorders

Practice Questions

Sedative, Hypnotic, and Anxiolytic Use Disorders

Practice Questions

Tobacco Use Disorder

Practice Questions

Hallucinogen-Related Disorders

Practice Questions

Substance Withdrawal Syndromes

Practice Questions

Pharmacotherapy for Substance Use Disorders

Practice Questions

Psychosocial Interventions

Practice Questions

Dual Diagnosis Management

Practice Questions

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