10 free EMT practice questions: Toxicology & Substance Use Emergencies

Acute alcohol intoxication with a declining level of consciousness: Intoxication is the reflex explanation for anyone with heavy alcohol use and is often right. The timing inverts it: the last drink was roughly 40 hours ago, so blood alcohol is falling or gone, and what the patient is showing is the absence of alcohol rather than its presence.

Wernicke encephalopathy from chronic thiamine deficiency: Wernicke encephalopathy is a genuine risk in chronic heavy drinkers and belongs in the differential. It presents with confusion, eye movement abnormalities, and unsteady gait rather than the autonomic picture of withdrawal, and it develops over a longer course than 40 hours.

Delirium tremens, which begins within 6 hours of the last drink: Delirium tremens is the severe end of exactly this process, so the category is right: the timeframe is not. It characteristically begins 48 to 96 hours after the last drink, which is why "within 6 hours" is the part that fails.

The ingestion occurred too recently for charcoal to be effective: Timing is a legitimate consideration for charcoal, but this option has the direction reversed: 20 minutes is well inside the window where charcoal has its best chance, since much of the drug is likely still sitting in the stomach. This reasoning would be sound several hours out, when most of the substance has already moved on and been absorbed. As written, the elapsed time actually argues in favor of charcoal, which is why the contraindication has to come from somewhere else.

The patient took an over-the-counter rather than a prescription medication: Whether a medication was bought over the counter or prescribed says nothing about whether charcoal binds it. That depends on the properties of the substance, and over-the-counter pain relievers are among the ingestions for which charcoal is considered. This option sorts drugs by where they were purchased, which is not a clinical variable. The key sorts by the patient's ability to protect the airway, which is.

Activated charcoal is only effective for ingested corrosive substances: This one is backwards in an instructive way: a caustic or corrosive ingestion is a classic contraindication to charcoal rather than an indication, because charcoal binds those substances poorly and obscures the view for the endoscopy that patient will need. Believing the reverse would have you giving charcoal in exactly the situation where it does the most harm. It also does not describe this patient, whose ingestion was an over-the-counter pain reliever.

Withhold naloxone entirely, since the intranasal route is unavailable: Withholding a drug is correct when there is a genuine contraindication to the drug itself: a known allergy, a condition the drug would worsen. There is no contraindication to naloxone here; the problem is the nostril, not the naloxone, and respirations of 4/min with pinpoint pupils is precisely the presentation the drug exists for. The key solves a route problem with a different route, while this option treats a route problem as though the medication were the issue.

Place naloxone under the tongue to be absorbed through the oral mucosa: Sublingual delivery is a real route, and nitroglycerin is the one every EMT knows, because those agents are formulated to absorb through oral mucosa. Naloxone is not made or approved for sublingual use, so absorption is unreliable, and this patient is unresponsive with a compromised airway, putting anything in the mouth to dissolve invites aspiration. The key uses a route naloxone is actually manufactured and approved for, in a patient who cannot protect their own airway.

Delay naloxone until the nosebleed has fully resolved: Waiting is reasonable when the treatment can safely wait, such as a stable patient or a non-urgent medication. Four breaths a minute is not survivable for long, and a nosebleed from a facial injury may not stop in the field at all, so this ties a time-critical intervention to an event that may never happen. The key delivers the drug now by a route that works, instead of holding it hostage to the nostril.

Nausea and occasional vomiting without other symptoms: Nausea alone does not contraindicate activated charcoal, though vomiting may require repeating the dose.

Passage of black, tarry stools without other symptoms: Black stools are a known adverse effect of activated charcoal, not a contraindication to giving it.

Chronic constipation with no associated abdominal pain: Constipation is an adverse effect of activated charcoal, not a reason to withhold it.

Dilated pupils: associated with sympathomimetic or anticholinergic overdose, not opioids.

Hypertension: seen with sympathomimetic or anticholinergic toxicity, whereas opioids typically cause hypotension.

Hyperthermia: associated with sympathomimetic or anticholinergic overdose, not opioid overdose.

Anticholinergic toxidrome (dry mouth, dilated pupils, agitation, rapid heart rate): Anticholinergic toxidrome produces dry mouth (opposite of salivation) and dilated pupils (opposite of pinpoint), plus tachycardia, not the presentation here.

Sympathomimetic toxidrome (dilated pupils, tachycardia, hypertension, agitation): Sympathomimetic toxidrome causes dilated pupils and agitation but not miosis, salivation, or the gastrointestinal signs present.

Sedative-hypnotic toxidrome (lethargy, respiratory depression, hypotension): Sedative-hypnotic toxidrome presents with lethargy and respiratory depression; it does not produce the autonomic signs (salivation, miosis, muscle twitching) observed here.

Administer high-flow oxygen by NRB to slow the rapid heart rate and reduce the patient's agitation: High-flow oxygen by NRB does not slow a stimulant-driven heart rate or calm sympathomimetic agitation. It does not address the physiology causing the presentation, and nothing in the assessment indicates hypoxia.

Apply physical restraints immediately to prevent the patient from causing harm to themselves or to the crew: Applying physical restraints to a hyperadrenergic patient who is not an immediate danger can worsen the underlying state and increase the risk of sudden cardiac complications, rather than making the situation safer.

Administer a dose of intranasal naloxone to reverse the effects of the powdered substance the patient used: Naloxone reverses opioids specifically. It has no effect on a stimulant-driven presentation like this one.

The naloxone has completely reversed the opioid effect, and the patient may now safely refuse further evaluation and transport: The reversal was neither complete nor durable: the patient became drowsy again within minutes, which shows the opioid effect persists and makes refusal unsafe.

The patient is now experiencing acute opioid withdrawal, which shows the overdose has resolved and the crisis has passed: The recurring drowsiness is re-sedation from continuing opioid effect, not withdrawal: withdrawal produces agitation, tachycardia, and gastrointestinal distress, not sedation, and the crisis is not over while re-sedation is occurring.

The recurring drowsiness indicates the naloxone dose was ineffective and a different medication is needed to reverse the substance: The naloxone worked: the patient aroused and breathing improved after the dose. The returning drowsiness reflects naloxone's shorter duration of action relative to the opioid, not an ineffective dose, and no alternative reversal medication exists at the EMT level: the correct response is transport with monitoring and repeat naloxone per protocol if respiratory depression recurs.

Withhold ventilatory support until naloxone takes effect: Waiting to see whether a drug works before adding support is reasonable when the patient is holding their own in the meantime: someone breathing adequately while a nitroglycerin dose takes effect. This patient is breathing 6 times a minute at 82% on room air, which is not holding anything; brain tissue is hypoxic for every second of that wait. The key beats it because ventilation and naloxone are not competing choices here, and ventilating is what keeps the patient alive during the minutes the naloxone needs.

Administer oral glucose: Oral glucose is the right answer for an altered patient with a low blood glucose who can still protect their own airway. Nothing points there: pinpoint pupils are an opioid finding, not a hypoglycemia finding, and an unresponsive patient breathing 6 times a minute cannot safely take anything by mouth. The key beats it because the findings name opioids specifically, and giving glucose would delay the ventilation this patient needs immediately.

Apply a tourniquet to the affected extremity: A tourniquet is the correct immediate action for life-threatening external hemorrhage from an extremity, where direct pressure cannot control the bleeding. This question describes no injury, no bleeding, and no trauma at all. The key beats it because there is nothing for a tourniquet to control, and the actual life threat on this call is a respiratory rate of 6.

Approach and administer intranasal naloxone: Pinpoint pupils and slow breathing look like an opioid overdose, and naloxone is right for that patient. The chemical odor and sprayer point to a pesticide exposure instead. Naloxone has no effect on cholinergic toxicity.

Begin positive pressure ventilations without protective equipment: Supporting this patient's breathing is genuinely the next step. The order matters. The same chemical soaking the coveralls can transfer onto an EMT who makes contact without protection first. Decontamination comes before hands-on ventilation.

Perform a rapid trauma assessment for open wounds: A trauma assessment doesn't fit this call, since there's no mechanism of injury described. It also doesn't address the contamination risk or the breathing problem.