AEMCA Toxicology and Substance Abuse 1 — Questions and Answers
Question 1: What is the antidote for acetaminophen (Tylenol) overdose?
- N-acetylcysteine (NAC) (Correct answer)
- Naloxone
- Flumazenil
- Activated charcoal alone
Correct answer: N-acetylcysteine (NAC)
N-acetylcysteine replenishes hepatic glutathione stores and prevents the hepatotoxicity caused by the toxic acetaminophen metabolite NAPQI.
Question 2: A patient presents with pinpoint pupils, decreased respirations, and altered mental status. Which class of drugs is most likely responsible?
- Stimulants (cocaine/amphetamines)
- Benzodiazepines
- Opioids (Correct answer)
- Anticholinergics
Correct answer: Opioids
The classic opioid toxidrome includes miosis (pinpoint pupils), respiratory depression, and altered mental status — the life-threatening triad.
Question 3: Which is the first-line pharmacological treatment for organophosphate (pesticide) poisoning in the prehospital setting?
- Naloxone
- Atropine (Correct answer)
- Flumazenil
- Physostigmine
Correct answer: Atropine
Atropine blocks muscarinic receptors and reverses the excessive cholinergic secretions (SLUDGE signs) caused by organophosphate poisoning.
Question 4: What is the appropriate initial dose of naloxone for an adult with suspected opioid overdose?
- 0.1 mg IV only
- 0.4–2 mg IV/IM/IN titrated to effect (Correct answer)
- 5–10 mg IV bolus
- 0.01 mg/kg IV push
Correct answer: 0.4–2 mg IV/IM/IN titrated to effect
Naloxone is given at 0.4–2 mg via IV, IM, or intranasal routes and titrated to restore adequate ventilation without precipitating withdrawal.
Question 5: A patient presents with hyperthermia, tachycardia, hypertension, dilated pupils, and severe agitation. Which toxidrome best describes this presentation?
- Opioid toxidrome
- Cholinergic toxidrome
- Sympathomimetic toxidrome (Correct answer)
- Sedative-hypnotic toxidrome
Correct answer: Sympathomimetic toxidrome
The sympathomimetic toxidrome, caused by cocaine or amphetamines, features hyperthermia, hypertension, tachycardia, mydriasis, and agitation from excess catecholamine activity.
Question 6: Which of the following signs is characteristic of the cholinergic (SLUDGE) toxidrome?
- Dry mouth and skin
- Urinary retention
- Excessive salivation and lacrimation (Correct answer)
- Mydriasis (dilated pupils)
Correct answer: Excessive salivation and lacrimation
SLUDGE (Salivation, Lacrimation, Urination, Defecation, GI distress, Emesis) describes the hypersecretory effects of excess acetylcholine in cholinergic toxicity.
Question 7: A patient has ingested a tricyclic antidepressant (TCA) overdose. What is the most dangerous immediate complication?
- Respiratory depression
- Cardiac dysrhythmias from sodium channel blockade (Correct answer)
- Acute kidney failure
- Liver failure within 24 hours
Correct answer: Cardiac dysrhythmias from sodium channel blockade
TCA overdose blocks cardiac sodium channels causing QRS widening and life-threatening ventricular dysrhythmias such as ventricular tachycardia and fibrillation.
AEMCA Toxicology and Substance Abuse 1
What is the antidote for acetaminophen (Tylenol) overdose?