Free NREMT Practice Questions
Toxicology
Overdose recognition, airway support, and targeted antidote decisions. Prioritize breathing and perfusion.
What you'll master
- ✓Toxidrome cues
- ✓Airway-first overdose actions
- ✓Naloxone decision timing
- ✓Scene safety and exposure control
Common misses
- –Chasing history instead of airway
- –Incorrect antidote timing
- –Missing recurrent hypoventilation
Sample questions.
25 free toxicology questions with answers and explanations. MedRelay's full question bank covers every NREMT domain, plus live scenarios that grade the decision, not just the answer.
Question 1
You respond to a garage where a 55-year-old male was found slumped over. His wife found him 30 minutes after he had been working alone with the garage door closed. On arrival he is conscious with confusion, headache, and nausea. SpO2 98%, HR 104. The garage has a running lawn mower inside. You move him outside. What is the critical management step beyond oxygen administration?
Why:Correct. CO poisoning requires: evacuation from the source, high-flow NRB oxygen regardless of SpO2 (SpO2 is unreliable), and assessment for other exposed persons. Family members, pets, and anyone in the structure must be evacuated. CO is odorless — the patient and others may not know the extent of exposure. SpO2 98% is a false reassurance.
Question 2
At a warehouse, two workers collapse after chemical exposure. Your partner wants to rush in. What should you do?
Why:Correct. Multiple collapses after chemical exposure indicate a hazardous scene. Stage, isolate, request hazmat, and avoid secondary contamination.
Question 3
At a mall corridor, a 45-year-old female has taken unknown pills. Which scene item is most useful for ED handoff?
Why:Correct. Medication containers can show drug names, quantities, and doses.
Question 4
At a college dorm, a 19-year-old female is unconscious with low glucose. Why should oral glucose be avoided?
Why:Correct. Oral glucose is unsafe when the patient cannot swallow or protect the airway.
Question 5
You respond to a 38-year-old male who intentionally ingested a large quantity of acetaminophen and alcohol 5 hours ago. He is conscious with GCS 14, mildly nauseated, HR 98, BP 118/76. He looks well. He says he only took aspirin and wine. However his girlfriend found an empty Tylenol bottle and an empty wine bottle. Why is his statement that he only took aspirin important to evaluate carefully?
Why:Correct. Patient misreporting of ingested substances is common in overdose — minimization, shame, confusion, and impaired cognition all contribute. Many patients conflate aspirin and Tylenol (acetaminophen). The empty Tylenol bottle is objective evidence that must be communicated to the receiving team. Acetaminophen has a deceptively benign initial presentation — the toxic window for N-acetylcysteine closes within 8-10 hours.
Question 6
You respond to an 18-year-old female who ingested approximately 30 diphenhydramine (Benadryl) tablets 1 hour ago. She is conscious with GCS 14, HR 138, BP 108/76, dry flushed skin, dilated pupils, urinary retention, and confusion. She is not vomiting. What toxidrome is this and can activated charcoal be administered?
Why:Correct. Diphenhydramine overdose produces anticholinergic toxidrome: dry flushed skin, dilated pupils, tachycardia, urinary retention, confusion, hyperthermia. The mnemonic applies. Activated charcoal within 1 hour with an intact gag reflex and medical direction may be appropriate. GCS 14 indicates adequate airway protection currently.
Question 7
You respond to a 43-year-old male found at home by his wife. He was complaining of visual changes and yellow halos around lights earlier today. He has a history of heart failure and takes digoxin. He has been nauseated and vomited twice. HR is 42, BP is 88/52, GCS is 11. What do the yellow-green visual halos combined with bradycardia and nausea indicate and what should you have immediately accessible throughout transport?
Why:Correct. Digoxin toxicity and AED readiness: digoxin toxicity causes bradyarrhythmias but also predisposes to ventricular fibrillation and other lethal arrhythmias. The AED must be immediately accessible throughout transport. The classic triad (xanthopsia, nausea/vomiting, bradyarrhythmia) confirms the diagnosis. Priority 1 ALS transport for Digibind. Do not attempt to slow the heart rate further — the bradycardia is from the toxicity.
Question 8
A patient sprayed with pepper spray is coughing and anxious. No airway swelling is present. What is appropriate care?
Why:Correct. Remove from exposure, provide fresh air, irrigate affected areas, and reassess airway and breathing.
Question 9
You respond to a 44-year-old female who reports progressive weakness, double vision, and difficulty swallowing for 3 days. She recently ate home-canned green beans. She has no fever. On assessment she has bilateral ptosis (drooping eyelids), symmetric facial weakness, and cannot raise her arms above shoulder height. GCS is 15. What toxin causes descending cranial nerve involvement without fever?
Why:Correct. Botulism: botulinum toxin blocks ACh release at neuromuscular junctions causing descending flaccid paralysis. Classic: cranial nerve involvement first (diplopia, ptosis, dysarthria, dysphagia) → descending limb weakness → respiratory failure. No fever (no active infection — preformed toxin ingested). Home-canned vegetables classic source. Priority 1 ALS transport — respiratory failure from diaphragm involvement is the primary risk.
Question 10
At a office lobby, a 57-year-old female has taken unknown pills. Which scene item is most useful for ED handoff?
Why:Correct. Medication containers can show drug names, quantities, and doses.
Question 11
You respond to a 19-year-old female who was brought in from a party. Friends say she mixed alcohol with a muscle relaxant (carisoprodol/Soma). She is very drowsy and difficult to arouse. RR is 6, SpO2 is 82%, GCS is 7. HR is 64, BP is 96/62. There are no drug paraphernalia suggesting opioids. What is the priority management?
Why:Correct. Carisoprodol is metabolized to meprobamate which has barbiturate-like CNS depressant properties. Combined CNS depression from carisoprodol and alcohol does not respond to naloxone. RR 6 with SpO2 82% is respiratory failure requiring immediate BVM ventilation. ALS intercept for airway management and supportive care.
Question 12
At a train platform, after naloxone, a patient wakes up angry and wants to leave. What should you explain?
Why:Correct. Naloxone can wear off before the opioid. Recurrent respiratory depression is possible.
Question 13
You respond to a 22-year-old female who ingested a large quantity of acetaminophen (Tylenol) in a suicide attempt 2 hours ago. She is conscious with GCS 14, mild nausea, HR 98, BP 116/74. She looks well. She says she feels fine and wants to go home. Her friend says she is overreacting. What is the critical reason this patient must be transported despite appearing well?
Why:Correct. Acetaminophen delayed hepatotoxicity: the current wellness is deceptive. NAPQI accumulation silently depletes hepatic glutathione during Phase 1. Hepatic failure develops in Phase 3 (72-96 hours) when treatment is too late. N-acetylcysteine (NAC) given within 8-10 hours is highly effective — after this window, liver failure may be irreversible. This patient's current appearance provides no reassurance. Transport urgently.
Question 14
At a soccer field, a 29-year-old female confused patient smells of alcohol. What assessment should not be skipped?
Why:Correct. Hypoglycemia can mimic intoxication and is a treatable EMT-B finding.
Question 15
You respond to a 44-year-old male who accidentally ingested antifreeze (ethylene glycol) approximately 2 hours ago. He mistook it for a sports drink. He currently appears moderately intoxicated with slurred speech and ataxia. HR 104, BP 128/78, GCS 13. He has no visual symptoms. What makes ethylene glycol uniquely dangerous and why is the 2-hour timeframe relevant?
Why:Correct. Ethylene glycol metabolism: ethylene glycol itself causes intoxication but its metabolites (glycolate, oxalate) cause the fatal organ damage. Oxalate causes calcium oxalate crystal deposition in the kidneys (renal failure) and brain. Fomepizole or ethanol competitively inhibit alcohol dehydrogenase preventing toxic metabolite formation — the earlier the better. Priority 1 ALS transport.
Question 16
A confused diabetic patient has glucose 62 mg/dL, can swallow, and took insulin without eating. What should you do?
Why:Correct. Low glucose with ability to swallow is an indication for oral glucose per EMT-B protocol.
Question 17
You respond to a 38-year-old female who ingested an unknown quantity of her prescribed lithium carbonate in a suicide attempt 3 hours ago. She is conscious with GCS 13. HR 56, BP 86/52. She has coarse tremors, ataxia, and slurred speech. She says her vision is blurry. Her BGL is 102. She is nauseated. Which symptom of lithium toxicity is most predictive of severe toxicity requiring hemodialysis?
Why:Correct. Lithium toxicity severity prediction: neurological symptoms (ataxia, coarse tremor, dysarthria, confusion) combined with cardiovascular compromise (bradycardia, hypotension) indicate moderate-severe toxicity. Severe toxicity (seizures, coma, cardiovascular collapse) requires hemodialysis. Serum lithium level guides definitive management at hospital. Priority 1 ALS transport for neurological and cardiac monitoring.
Question 18
You respond to a 48-year-old male who was working in a car garage and has been feeling progressively unwell for several hours. He reports headache, dizziness, and nausea. Two coworkers have similar symptoms. The garage has multiple cars running for emissions testing in an enclosed space. SpO2 reads 98% on your oximeter. What is the clinical significance of his SpO2 reading and why is your assessment priority different from a patient with chest pain and SpO2 98%?
Why:Correct. CO poisoning and false SpO2: standard pulse oximeters use two wavelengths that cannot distinguish OxyHb from COHb — both absorb identically. A patient with 60% COHb can display SpO2 99%. Multiple affected workers plus enclosed space with running vehicles = CO poisoning. Apply 100% NRB oxygen immediately — this accelerates CO elimination by competing for hemoglobin binding. SpO2 provides no diagnostic reassurance in this context.
Question 19
You respond to a 61-year-old male who ingested his prescribed digoxin tablets — the entire weekly pill organizer worth — intentionally. He is conscious with GCS 13. HR is 36, BP is 72/44. He reports seeing yellow halos around all the lights. He has severe nausea. The AED is attached and monitoring is active. Why must you have the AED immediately ready throughout transport for this patient?
Why:Correct. Digoxin toxicity and lethal arrhythmia risk: digoxin toxicity causes bradyarrhythmias (AV block, junctional rhythms) AND simultaneously increases ventricular excitability — creating risk for VF, VT, and bidirectional VT. The AED must be immediately ready throughout transport. Xanthopsia (yellow halos), nausea, bradycardia, and hypotension confirm severe toxicity. Priority 1 ALS for Digibind. Do not attempt additional rate-slowing.
Question 20
You respond to a 31-year-old male who is confused and agitated. His friends say he used MDMA (ecstasy) about 3 hours ago. He also drank heavily. His temperature is 40.1 degrees C. HR is 178, BP is 162/108. He has spontaneous clonus in his lower extremities. He is sweating profusely. In addition to cooling for the hyperthermia, what is the primary prehospital concern related to his spontaneous clonus?
Why:Correct. Serotonin syndrome clonus and respiratory risk: spontaneous clonus confirms SS. Beyond hyperthermia, severe serotonin syndrome with muscle rigidity can cause respiratory failure — the intercostal and diaphragmatic muscles can be affected by the neuromuscular hyperexcitability. Aggressive cooling, ALS urgently for benzodiazepines (reduce neuromuscular activity and serotonergic excitability), and close respiratory monitoring.
Question 21
At a apartment hallway, a 44-year-old male exposed to pepper spray has eye burning but no airway distress. What is appropriate?
Why:Correct. Remove from exposure, irrigate affected areas, and reassess airway and breathing.
Question 22
At a train platform, you smell exhaust in a garage and find a confused patient with a normal pulse ox. What should you suspect?
Why:Correct. Pulse oximetry can be falsely normal in carbon monoxide exposure.
Question 23
You enter a home with several dizzy patients and a running generator nearby. What should you do first?
Why:Correct. Suspected carbon monoxide exposure requires removal from the environment, oxygen, and additional resources.
Question 24
You respond to a 29-year-old male found unconscious at a party. His friends say he took MDMA (ecstasy) about 3 hours ago. He is unresponsive, GCS 6, HR 164, BP 162/104, temperature 41.2 degrees C, pupils dilated bilaterally. He is diaphoretic and having repetitive jerking muscle movements. His Na level from a rapid test reads 122 mEq/L. What two concurrent toxicological processes explain his presentation?
Why:Correct. MDMA causes serotonin syndrome (from massive serotonin release) producing hyperthermia, tachycardia, diaphoresis, clonus, and AMS. Simultaneously MDMA causes inappropriate ADH release and users drink excessive water causing dilutional hyponatremia. Na 122 causes cerebral edema. Both processes require concurrent treatment. Aggressive cooling plus ALS for Na correction.
Question 25
An opioid overdose patient is breathing 6 times per minute with pinpoint pupils. What should you do first?
Why:Correct. Inadequate breathing is the immediate threat. Ventilate first, then administer naloxone per protocol.
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