LATEST MEDICAL TOXICOLOGY
CERTIFICATION EXAM OFFERED BY
AMERICAN BOARD OF PREVENTIVE MEDICINE
| COMPLETE EXAM Q&A WITH RATIONALES
1. A 35-year-old male presents 2 hours after ingestion
of 50 tablets of extended-release acetaminophen
(500 mg each). Serum acetaminophen level is 200
mcg/mL at 4 hours. Which is the most appropriate
next step?
A) Activated charcoal 50 g orally
B) N-acetylcysteine (NAC) IV infusion
C) Hemodialysis
D) Observation only
Correct answer: B
Rationale: Acetaminophen level >150 mcg/mL at 4
hours after ingestion of a potentially toxic dose
requires NAC therapy to prevent hepatotoxicity.
2. A 20-year-old female is brought to the emergency
department after ingesting an unknown amount of
diphenhydramine. She is agitated, has hallucinations,
and a heart rate of 140 bpm. ECG shows QRS
,duration of 120 ms. Which is the most appropriate
next step?
A) Sodium bicarbonate IV push
B) Flumazenil
C) Naloxone
D) Physostigmine
Correct answer: A
Rationale: Sodium bicarbonate is first-line for QRS
widening (>100 ms) from sodium channel blockade
(tricyclic antidepressants, diphenhydramine,
quinidine).
3. A 45-year-old male presents with confusion,
vomiting, and abdominal pain. He works at a battery
recycling plant. Laboratory studies show normocytic
anemia, basophilic stippling, and serum lead level of
95 mcg/dL. Which is the most appropriate treatment?
A) Succimer (DMSA) orally
B) Calcium disodium EDTA IV
C) Dimercaprol (BAL) IM + CaNa2EDTA IV
D) D-penicillamine orally
Correct answer: C
,Rationale: Symptomatic lead poisoning with blood
lead >70 mcg/dL and encephalopathy requires
hospitalization and chelation with BAL + CaNa2EDTA.
4. A 55-year-old male with end-stage renal disease on
hemodialysis presents with slurred speech, ataxia,
and confusion after eating a large amount of fish.
Which heavy metal is most likely responsible?
A) Mercury (methylmercury)
B) Lead
C) Arsenic
D) Cadmium
Correct answer: A
Rationale: Methylmercury from contaminated fish
(tuna, shark, swordfish) causes neurologic symptoms
(ataxia, dysarthria, paresthesias, visual field
constriction).
5. A 30-year-old female presents after intentional
ingestion of an unknown amount of verapamil. She is
hypotensive (BP 80/50) with heart rate 45 bpm. Which
is the most appropriate initial treatment?
A) Atropine
B) Calcium gluconate
, C) Glucagon
D) Norepinephrine infusion
Correct answer: B
Rationale: Calcium gluconate (or calcium chloride) is
first-line for calcium channel blocker toxicity
(verapamil, diltiazem) to increase inotropy and heart
rate.
6. A 25-year-old male presents with weakness,
nausea, and abdominal pain after drinking
"moonshine" at a party. He has visual disturbances
(central scotoma) and a wide anion gap metabolic
acidosis (anion gap 30). Which is the most likely
toxin?
A) Methanol
B) Ethylene glycol
C) Isopropanol
D) Ethanol
Correct answer: A
Rationale: Methanol toxicity causes visual
disturbances (central scotoma, blindness) and high
anion gap metabolic acidosis. Treatment is
fomepizole or ethanol and hemodialysis.
CERTIFICATION EXAM OFFERED BY
AMERICAN BOARD OF PREVENTIVE MEDICINE
| COMPLETE EXAM Q&A WITH RATIONALES
1. A 35-year-old male presents 2 hours after ingestion
of 50 tablets of extended-release acetaminophen
(500 mg each). Serum acetaminophen level is 200
mcg/mL at 4 hours. Which is the most appropriate
next step?
A) Activated charcoal 50 g orally
B) N-acetylcysteine (NAC) IV infusion
C) Hemodialysis
D) Observation only
Correct answer: B
Rationale: Acetaminophen level >150 mcg/mL at 4
hours after ingestion of a potentially toxic dose
requires NAC therapy to prevent hepatotoxicity.
2. A 20-year-old female is brought to the emergency
department after ingesting an unknown amount of
diphenhydramine. She is agitated, has hallucinations,
and a heart rate of 140 bpm. ECG shows QRS
,duration of 120 ms. Which is the most appropriate
next step?
A) Sodium bicarbonate IV push
B) Flumazenil
C) Naloxone
D) Physostigmine
Correct answer: A
Rationale: Sodium bicarbonate is first-line for QRS
widening (>100 ms) from sodium channel blockade
(tricyclic antidepressants, diphenhydramine,
quinidine).
3. A 45-year-old male presents with confusion,
vomiting, and abdominal pain. He works at a battery
recycling plant. Laboratory studies show normocytic
anemia, basophilic stippling, and serum lead level of
95 mcg/dL. Which is the most appropriate treatment?
A) Succimer (DMSA) orally
B) Calcium disodium EDTA IV
C) Dimercaprol (BAL) IM + CaNa2EDTA IV
D) D-penicillamine orally
Correct answer: C
,Rationale: Symptomatic lead poisoning with blood
lead >70 mcg/dL and encephalopathy requires
hospitalization and chelation with BAL + CaNa2EDTA.
4. A 55-year-old male with end-stage renal disease on
hemodialysis presents with slurred speech, ataxia,
and confusion after eating a large amount of fish.
Which heavy metal is most likely responsible?
A) Mercury (methylmercury)
B) Lead
C) Arsenic
D) Cadmium
Correct answer: A
Rationale: Methylmercury from contaminated fish
(tuna, shark, swordfish) causes neurologic symptoms
(ataxia, dysarthria, paresthesias, visual field
constriction).
5. A 30-year-old female presents after intentional
ingestion of an unknown amount of verapamil. She is
hypotensive (BP 80/50) with heart rate 45 bpm. Which
is the most appropriate initial treatment?
A) Atropine
B) Calcium gluconate
, C) Glucagon
D) Norepinephrine infusion
Correct answer: B
Rationale: Calcium gluconate (or calcium chloride) is
first-line for calcium channel blocker toxicity
(verapamil, diltiazem) to increase inotropy and heart
rate.
6. A 25-year-old male presents with weakness,
nausea, and abdominal pain after drinking
"moonshine" at a party. He has visual disturbances
(central scotoma) and a wide anion gap metabolic
acidosis (anion gap 30). Which is the most likely
toxin?
A) Methanol
B) Ethylene glycol
C) Isopropanol
D) Ethanol
Correct answer: A
Rationale: Methanol toxicity causes visual
disturbances (central scotoma, blindness) and high
anion gap metabolic acidosis. Treatment is
fomepizole or ethanol and hemodialysis.
