ABT Clinical Toxicology 1 — Questions and Answers
Question 1: Which antidote is used to treat acetaminophen overdose by replenishing glutathione stores?
- N-acetylcysteine (Correct answer)
- Flumazenil
- Naloxone
- Atropine
Correct answer: N-acetylcysteine
N-acetylcysteine (NAC) is the standard antidote for acetaminophen overdose, acting as a glutathione precursor to prevent hepatotoxicity.
Question 2: The Rumack-Matthew nomogram is used to assess overdose risk from which substance?
- Salicylates
- Acetaminophen (Correct answer)
- Tricyclic antidepressants
- Opioids
Correct answer: Acetaminophen
The Rumack-Matthew nomogram plots serum acetaminophen concentration against time post-ingestion to predict hepatotoxicity risk.
Question 3: Which toxidrome is characterized by miosis, bradycardia, excessive secretions, and bronchospasm?
- Sympathomimetic
- Anticholinergic
- Cholinergic (Correct answer)
- Opioid
Correct answer: Cholinergic
The cholinergic toxidrome results from excess acetylcholine activity and is remembered by the mnemonic SLUDGE (Salivation, Lacrimation, Urination, Defecation, GI distress, Emesis).
Question 4: Which specific antidote reverses benzodiazepine-induced CNS and respiratory depression?
- Naloxone
- Physostigmine
- Flumazenil (Correct answer)
- Pyridoxine
Correct answer: Flumazenil
Flumazenil is a competitive benzodiazepine receptor antagonist used to reverse benzodiazepine sedation and respiratory depression.
Question 5: A patient presents with altered mental status, metabolic acidosis, and an elevated osmol gap. Which toxin is most likely responsible?
- Aspirin
- Isoniazid
- Ethylene glycol (Correct answer)
- Digoxin
Correct answer: Ethylene glycol
Ethylene glycol ingestion causes an elevated osmol gap early and an elevated anion gap metabolic acidosis as it is metabolized to oxalic acid.
Question 6: Digoxin toxicity is potentiated by which electrolyte abnormality?
- Hyperkalemia
- Hypokalemia (Correct answer)
- Hypernatremia
- Hypercalcemia
Correct answer: Hypokalemia
Hypokalemia increases digoxin toxicity because potassium and digoxin compete for the same binding site on the Na+/K+-ATPase pump.
ABT Clinical Toxicology 1
Which antidote is used to treat acetaminophen overdose by replenishing glutathione stores?