MCQ on Drug Overdose Management

🟢 Easy (1–20)

1. What is the first step in managing a suspected drug overdose?
   a) Administer antidote
   b) Induce vomiting
   c) Ensure airway, breathing, and circulation (ABC) ✅
   d) Start dialysis
   Explanation: Stabilizing the patient’s vital functions is always the first priority.
2. Which drug is used as an antidote for opioid overdose?
   a) Flumazenil
   b) Naloxone ✅
   c) Atropine
   d) Acetylcysteine
   Explanation: Naloxone is a competitive opioid antagonist.
3. Which symptom is most indicative of opioid overdose?
   a) Dilated pupils
   b) Pinpoint pupils ✅
   c) Hypertension
   d) Seizures
   Explanation: Pinpoint pupils are classic signs of opioid toxicity.
4. What is the antidote for benzodiazepine overdose?
   a) Naloxone
   b) Acetylcysteine
   c) Flumazenil ✅
   d) Atropine
   Explanation: Flumazenil is a specific benzodiazepine receptor antagonist.
5. Which route is commonly used to administer naloxone in emergencies?
   a) Oral
   b) Intravenous ✅
   c) Subcutaneous
   d) Inhalational
   Explanation: IV route provides rapid reversal in critical situations.
6. Which of the following is used in paracetamol (acetaminophen) overdose?
   a) Atropine
   b) Flumazenil
   c) Acetylcysteine ✅
   d) Naloxone
   Explanation: Acetylcysteine replenishes glutathione and prevents liver damage.
7. What is a common sign of salicylate (aspirin) overdose?
   a) Respiratory alkalosis ✅
   b) Metabolic alkalosis
   c) Bradycardia
   d) Hyperkalemia
   Explanation: Salicylates initially cause hyperventilation leading to respiratory alkalosis.
8. Activated charcoal is most effective if given within:
   a) 24 hours
   b) 8 hours
   c) 4 hours
   d) 1 hour ✅
   Explanation: Activated charcoal is most effective within the first hour of ingestion.
9. Which is NOT a common feature of TCA (tricyclic antidepressant) overdose?
   a) Seizures
   b) Cardiac arrhythmias
   c) Hypotension
   d) Hypertension ✅
   Explanation: TCAs cause hypotension, not hypertension.
10. Which electrolyte imbalance is common in digoxin overdose?
    a) Hypocalcemia
    b) Hypokalemia
    c) Hyperkalemia ✅
    d) Hyponatremia
    Explanation: Digoxin toxicity often presents with hyperkalemia due to Na+/K+ ATPase inhibition.
11. Which poison has a characteristic “garlic” odor on the breath?
    a) Cyanide
    b) Arsenic ✅
    c) Methanol
    d) Ethanol
    Explanation: Arsenic poisoning can give a garlic-like odor to breath and stool.
12. Which vital sign abnormality is most common in beta-blocker overdose?
    a) Tachycardia
    b) Hypertension
    c) Bradycardia ✅
    d) Fever
    Explanation: Beta-blockers slow down heart rate.
13. Which agent is used as an antidote for warfarin overdose?
    a) Vitamin C
    b) Vitamin K ✅
    c) Iron
    d) Calcium
    Explanation: Vitamin K helps restore clotting factor synthesis inhibited by warfarin.
14. Which medication is used to treat methanol poisoning?
    a) Ethanol ✅
    b) Acetylcysteine
    c) Naloxone
    d) Salbutamol
    Explanation: Ethanol competes with methanol for alcohol dehydrogenase, preventing toxic metabolite formation.
15. Which of the following causes “cherry red” skin in overdose?
    a) Carbon monoxide ✅
    b) Cyanide
    c) Lead
    d) Iron
    Explanation: CO poisoning causes cherry-red coloration due to carboxyhemoglobin.
16. Which drug overdose can cause severe lactic acidosis?
    a) Theophylline
    b) Methanol
    c) Cyanide ✅
    d) Ibuprofen
    Explanation: Cyanide inhibits cellular respiration, leading to lactic acidosis.
17. Which of the following is contraindicated in corrosive poison ingestion?
    a) IV fluids
    b) Gastric lavage ✅
    c) Antiemetics
    d) Airway management
    Explanation: Gastric lavage can worsen tissue damage.
18. Which class of drugs can cause serotonin syndrome in overdose?
    a) NSAIDs
    b) SSRIs ✅
    c) Beta-blockers
    d) Antacids
    Explanation: Excess serotonergic activity can lead to serotonin syndrome.
19. What is the preferred treatment for iron overdose?
    a) Deferoxamine ✅
    b) Chelation with EDTA
    c) Hemodialysis
    d) Flumazenil
    Explanation: Deferoxamine binds iron and promotes its excretion.
20. Which of the following substances causes “anticholinergic toxidrome”?
    a) Atropine ✅
    b) Opioids
    c) Benzodiazepines
    d) Salicylates
    Explanation: Atropine blocks muscarinic receptors causing anticholinergic effects.

🟡 Moderate (21–40)

21. Which of the following drugs can cause hypoglycemia in overdose?
    a) Beta-blockers ✅
    b) Calcium channel blockers
    c) Theophylline
    d) Lithium
    Explanation: Beta-blockers can mask or cause hypoglycemia, especially in children.
22. Which lab test is critical in paracetamol overdose assessment?
    a) LFT
    b) INR
    c) Serum paracetamol level ✅
    d) Blood urea
    Explanation: Paracetamol level determines the need for antidote using the Rumack-Matthew nomogram.
23. A patient with methanol poisoning may develop which complication?
    a) Renal failure
    b) Pulmonary fibrosis
    c) Blindness ✅
    d) Hypercalcemia
    Explanation: Methanol is metabolized to formaldehyde and formic acid, damaging the optic nerve.
24. Which drug is used in cyanide poisoning along with oxygen?
    a) Atropine
    b) Sodium nitrite ✅
    c) Flumazenil
    d) Magnesium sulfate
    Explanation: Sodium nitrite induces methemoglobinemia, which binds cyanide.
25. What is the antidote for isoniazid (INH) overdose?
    a) Vitamin K
    b) Vitamin C
    c) Pyridoxine ✅
    d) Thiamine
    Explanation: Pyridoxine replenishes GABA production lost due to INH toxicity.
26. Which of the following drugs is not effectively removed by hemodialysis?
    a) Lithium
    b) Methanol
    c) Theophylline
    d) Digoxin ✅
    Explanation: Digoxin is highly tissue-bound and not effectively removed by dialysis.
27. In organophosphate poisoning, atropine is given to reverse:
    a) CNS depression
    b) Respiratory depression
    c) Muscarinic symptoms ✅
    d) Nicotinic symptoms
    Explanation: Atropine blocks muscarinic receptors, relieving salivation, bradycardia, etc.
28. Which medication overdose commonly leads to QT prolongation?
    a) Paracetamol
    b) Citalopram ✅
    c) Morphine
    d) Amoxicillin
    Explanation: Citalopram, an SSRI, is known to prolong QT at high doses.
29. Which of the following overdose causes metabolic acidosis with an increased anion gap?
    a) Acetaminophen
    b) Ethylene glycol ✅
    c) Diphenhydramine
    d) Diazepam
    Explanation: Ethylene glycol metabolizes into glycolic and oxalic acid, causing acidosis.
30. Which agent is most appropriate to alkalinize urine in phenobarbital overdose?
    a) Potassium chloride
    b) Calcium gluconate
    c) Sodium bicarbonate ✅
    d) Ammonium chloride
    Explanation: Sodium bicarbonate enhances phenobarbital elimination via urinary alkalinization.
31. Which symptom is least likely in serotonin syndrome?
    a) Muscle rigidity
    b) Hyperthermia
    c) Bradycardia ✅
    d) Agitation
    Explanation: Serotonin syndrome causes tachycardia, not bradycardia.
32. Which of the following is contraindicated in TCA overdose?
    a) Activated charcoal
    b) Gastric lavage
    c) Sodium bicarbonate
    d) Physostigmine ✅
    Explanation: Physostigmine may worsen cardiac conduction and seizures in TCA toxicity.
33. Which class of drugs causes “sympathomimetic toxidrome”?
    a) Opioids
    b) SSRIs
    c) Cocaine and amphetamines ✅
    d) Anticholinergics
    Explanation: These drugs mimic sympathetic stimulation.
34. Which vitamin is given in ethylene glycol toxicity?
    a) Folic acid
    b) Pyridoxine
    c) Thiamine
    d) Both C and D ✅
    Explanation: Thiamine and pyridoxine help shunt toxic metabolites to non-toxic pathways.
35. Which of the following does not cause miosis in overdose?
    a) Opioids
    b) Clonidine
    c) Organophosphates
    d) Amphetamines ✅
    Explanation: Amphetamines cause mydriasis (pupil dilation), not miosis.
36. Which complication is most likely after chronic lithium overdose?
    a) Pulmonary edema
    b) Encephalopathy ✅
    c) Hepatitis
    d) Anaphylaxis
    Explanation: Chronic lithium toxicity affects the central nervous system, causing confusion and tremor.
37. Which antidote works by chelating heavy metals like lead and mercury?
    a) Deferoxamine
    b) EDTA ✅
    c) Flumazenil
    d) Pyridoxine
    Explanation: EDTA is a chelating agent used for lead poisoning.
38. Which common household product can cause methemoglobinemia if ingested?
    a) Vinegar
    b) Hydrogen peroxide
    c) Nitrite-containing meat preservatives ✅
    d) Baking soda
    Explanation: Nitrites oxidize hemoglobin to methemoglobin, which cannot carry oxygen.
39. Which poison causes “blue line” on the gums in chronic exposure?
    a) Mercury
    b) Arsenic
    c) Lead ✅
    d) Copper
    Explanation: A Burtonian line is associated with chronic lead poisoning.
40. Which of the following is a cholinesterase reactivator used in organophosphate poisoning?
    a) Atropine
    b) Pralidoxime ✅
    c) Flumazenil
    d) Physostigmine
    Explanation: Pralidoxime reactivates acetylcholinesterase bound by organophosphates.

🔴 Hard (41–50)

41. Which toxic alcohol causes both metabolic acidosis and oxalate crystal deposition in urine?
    a) Methanol
    b) Ethanol
    c) Ethylene glycol ✅
    d) Isopropanol
    Explanation: Ethylene glycol forms oxalate crystals in renal tubules, leading to renal failure and acidosis.
42. In digoxin overdose, which of the following is a specific treatment?
    a) Atropine
    b) Digoxin-specific antibody fragments (Fab) ✅
    c) Sodium bicarbonate
    d) Beta-blockers
    Explanation: Digoxin-specific Fab binds to digoxin and neutralizes its toxic effects.
43. Which of the following symptoms is NOT typically associated with lithium toxicity?
    a) Tremors
    b) Seizures
    c) Diarrhea
    d) Hyperglycemia ✅
    Explanation: Lithium toxicity typically affects neurological and gastrointestinal systems, not blood glucose.
44. Which of the following drugs has a narrow therapeutic index and a high risk of toxicity?
    a) Amoxicillin
    b) Theophylline ✅
    c) Ibuprofen
    d) Acetaminophen
    Explanation: Theophylline has a narrow safety margin, and serum levels must be monitored.
45. Which ECG finding is characteristic of TCA overdose?
    a) Peaked T waves
    b) QT shortening
    c) Widened QRS complex ✅
    d) ST depression
    Explanation: TCAs block cardiac sodium channels, resulting in a widened QRS complex.
46. In cyanide poisoning, the administration of sodium thiosulfate acts by:
    a) Competing with cyanide at cytochrome oxidase
    b) Converting cyanide to thiocyanate ✅
    c) Chelating cyanide directly
    d) Oxidizing hemoglobin
    Explanation: Sodium thiosulfate provides sulfur groups to convert cyanide to less toxic thiocyanate.
47. Which of the following is a poor candidate for activated charcoal due to poor adsorption?
    a) Phenobarbital
    b) Iron ✅
    c) Carbamazepine
    d) Theophylline
    Explanation: Iron is poorly adsorbed by activated charcoal; alternative treatments like chelation are needed.
48. Which of the following is used in beta-blocker overdose with hypotension and bradycardia?
    a) Flumazenil
    b) Calcium gluconate
    c) Glucagon ✅
    d) Naloxone
    Explanation: Glucagon increases cAMP independent of beta-receptors, improving heart rate and contractility.
49. Which statement about serotonin syndrome is true?
    a) It is caused by dopamine deficiency
    b) It requires months to develop
    c) It presents with clonus and hyperreflexia ✅
    d) It leads to respiratory depression
    Explanation: Serotonin syndrome is an acute condition marked by neuromuscular hyperactivity.
50. A “snowfield vision” is a classical symptom of overdose with:
    a) Cocaine
    b) Theophylline
    c) Methanol ✅
    d) Lead
    Explanation: Methanol causes optic nerve damage, leading to visual disturbances, described as “snowfield” vision.