General Management, Decontamination, and Antidotes Practice Questions

25 multiple-choice questions on General management, decontamination, and antidotes for paramedic and EMT students, from Chapter 28 (Toxicology). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

25 practice questions

1. The first priority in managing any poisoned patient after scene safety is:

   1. A. Identifying the exact poison taken
   2. B. Giving the specific antidote
   3. C. Airway, breathing, and circulation
   4. D. Decontaminating the skin and eyes
   Show answer

   Answer: C. Airway, breathing, and circulation

   Most poisoned patients die of airway loss, hypoventilation, or shock, and supportive care saves more lives than antidotes. Identifying the toxin comes after the ABCs are secured.

2. A 40-year-old overdose patient has a GCS of 6, snoring respirations, and vomitus in the mouth. The priority is to:

   1. A. Suction and support ventilation
   2. B. Give activated charcoal by mouth
   3. C. Obtain the pill bottles from the home
   4. D. Start an IV and draw blood samples
   Show answer

   Answer: A. Suction and support ventilation

   An unprotected airway with vomitus risks aspiration, and suction plus ventilation come first. Charcoal is contraindicated in a patient who cannot protect the airway.

3. Every patient with an altered mental status from a suspected overdose should have:

   1. A. Flumazenil given empirically
   2. B. Activated charcoal administered
   3. C. Gastric lavage performed
   4. D. A blood glucose level checked
   Show answer

   Answer: D. A blood glucose level checked

   Hypoglycemia mimics intoxication and is quickly reversible, and some toxins such as sulfonylureas and alcohol cause it. Empiric flumazenil can trigger seizures.

4. In the hospital, repeated doses of activated charcoal every few hours are used mainly for which overdoses?

   1. A. Iron, lithium, and potassium chloride tablets
   2. B. Carbamazepine, phenobarbital, theophylline
   3. C. Methanol, ethylene glycol, and isopropanol
   4. D. Drain cleaners and other alkalis
   Show answer

   Answer: B. Carbamazepine, phenobarbital, theophylline

   Multiple-dose activated charcoal can speed removal of a few drugs that recirculate through the gut or are absorbed slowly, chiefly carbamazepine, phenobarbital, dapsone, quinine, and theophylline. Iron, lithium, and potassium are poorly adsorbed by charcoal, so repeating it adds nothing. Toxic alcohols are absorbed too quickly and bind poorly. Caustics are a contraindication.

5. A man swallowed 30 sustained-release tablets 2 hours ago and is alert with a protected airway. Medical control still orders activated charcoal, mainly because:

   1. A. Charcoal binds better after an hour
   2. B. Sustained-release drugs are less toxic
   3. C. Pills keep releasing drug for hours
   4. D. It neutralizes the stomach acid first
   Show answer

   Answer: C. Pills keep releasing drug for hours

   Charcoal works best within 1 hour, but sustained-release and enteric-coated tablets keep releasing drug in the gut for hours, so a later dose can still bind a useful amount. Charcoal does not bind better as time passes. Sustained-release products are not less toxic; their effects are delayed and prolonged. Charcoal adsorbs drugs and does not act by neutralizing acid.

6. Activated charcoal is most effective when given within:

   1. A. 1 hour of ingestion
   2. B. 6 hours of ingestion
   3. C. 12 hours of ingestion
   4. D. 24 hours of ingestion
   Show answer

   Answer: A. 1 hour of ingestion

   Benefit falls quickly once the drug has left the stomach. Later doses may help with sustained-release or slowly absorbed drugs, but that is a medical control decision.

7. A bystander asks whether a cathartic such as sorbitol should be given alone to a patient who swallowed pills. Current toxicology guidance says this is:

   1. A. Advised for every pill overdose
   2. B. Required before activated charcoal
   3. C. Not recommended as a treatment
   4. D. Preferred over activated charcoal
   Show answer

   Answer: C. Not recommended as a treatment

   Position statements from clinical toxicology groups found no evidence that a cathartic alone improves outcome, and repeated doses can cause dehydration and electrolyte problems, so cathartics are not used as a treatment. They are not needed before charcoal, and they do not replace it when charcoal is indicated.

8. A 19-year-old swallowed drain cleaner 15 minutes ago and is drooling. Regarding activated charcoal, you should:

   1. A. Give 1 g/kg quickly before burns develop
   2. B. Give it mixed with milk to soothe the throat
   3. C. Give half the dose to limit vomiting
   4. D. Withhold it; caustics are a contraindication
   Show answer

   Answer: D. Withhold it; caustics are a contraindication

   Charcoal does not bind caustics, obscures endoscopy, and vomiting re-exposes the esophagus. Caustics, hydrocarbons, and an unprotected airway are the main contraindications.

9. A patient with a drug overdose is still seizing after two doses of midazolam. Phenytoin is a poor next choice for seizures caused by poisoning because it:

   1. A. Seldom stops toxin-induced seizures
   2. B. Is far too sedating to use in the field
   3. C. Must be mixed in dextrose to be given
   4. D. Causes dangerous hyperkalemia
   Show answer

   Answer: A. Seldom stops toxin-induced seizures

   Toxin-induced seizures are usually driven by GABA loss or excess stimulation, and phenytoin works poorly on them; it can even worsen toxicity from sodium-channel blockers such as tricyclics. Benzodiazepines are first line, followed by drugs such as phenobarbital or propofol in the hospital. Phenytoin is not unusually sedating, it must be mixed in saline because it precipitates in dextrose, and it does not raise potassium.

10. The most common adverse effect of activated charcoal is:

    1. A. Diarrhea
    2. B. Vomiting
    3. C. Hypotension
    4. D. Hypoglycemia
    Show answer

    Answer: B. Vomiting

    Charcoal is gritty and unpalatable and often causes vomiting, which is why airway protection matters. It is more likely to cause constipation than diarrhea.

11. Gastric lavage in the prehospital setting is:

    1. A. The preferred first step for pill ingestions
    2. B. Required before giving activated charcoal
    3. C. Not routinely performed
    4. D. Indicated for all caustic ingestions
    Show answer

    Answer: C. Not routinely performed

    Lavage has limited benefit and risks aspiration and esophageal injury. It is reserved for rare hospital cases of recent life-threatening ingestion.

12. Whole bowel irrigation with polyethylene glycol may be used in the hospital for:

    1. A. Caustic ingestions and swallowed hydrocarbons such as gasoline
    2. B. Iron, lithium, sustained-release pills, and body packers
    3. C. Opioid overdose with severe respiratory depression
    4. D. Any pill ingestion within 1 hour of hospital arrival
    Show answer

    Answer: B. Iron, lithium, sustained-release pills, and body packers

    These are poorly bound by charcoal or released slowly, so flushing the gut is an option. Caustics and hydrocarbons are not treated this way.

13. A worker is splashed in both eyes with an industrial chemical. The best initial management is:

    1. A. Patch both eyes and transport immediately
    2. B. Irrigate briefly and apply an antibiotic ointment
    3. C. Neutralize the chemical with a weak buffer solution
    4. D. Irrigate with water or saline for 20+ minutes
    Show answer

    Answer: D. Irrigate with water or saline for 20+ minutes

    Prolonged irrigation is the most important treatment, and alkalis need longer, often an hour or more. Neutralizing agents generate heat, and patching traps the chemical.

14. Skin decontamination after a toxic liquid exposure should include:

    1. A. Removing clothing, flushing with copious water
    2. B. Wiping the skin with alcohol-soaked pads
    3. C. Applying a neutralizing cream to the area first
    4. D. Covering the skin with a dry sterile dressing
    Show answer

    Answer: A. Removing clothing, flushing with copious water

    Removing clothing eliminates much of the contaminant, and large-volume water dilutes and removes the rest. Wiping with alcohol can increase absorption of some chemicals. A neutralizing cream can cause a heat-producing reaction and delays flushing. A dry dressing leaves the chemical in contact with the skin.

15. A patient is given naloxone for suspected opioid toxicity, but it turns out she took only a large dose of a benzodiazepine. The expected response to the naloxone is:

    1. A. Full return of consciousness
    2. B. Worsened respiratory depression
    3. C. Little or no change in breathing
    4. D. Benzodiazepine withdrawal seizures
    Show answer

    Answer: C. Little or no change in breathing

    Naloxone is a pure opioid receptor antagonist and has no effect at benzodiazepine (GABA-A) receptors, so a benzodiazepine-only overdose will not respond. That is why naloxone is safe to give empirically when opioids are suspected. It does not cause benzodiazepine withdrawal and does not deepen respiratory depression. Flumazenil, not naloxone, is the benzodiazepine antagonist.

16. A 45-year-old with an unknown overdose is somnolent with RR 14. A bystander says she takes alprazolam daily. Flumazenil should be avoided mainly because it can:

    1. A. Precipitate seizures in dependent or TCA patients
    2. B. Cause profound respiratory depression and apnea
    3. C. Worsen opioid toxicity and deepen the miosis
    4. D. Produce severe hypoglycemia within minutes
    Show answer

    Answer: A. Precipitate seizures in dependent or TCA patients

    Reversing benzodiazepines removes seizure protection in chronic users and in TCA overdose. It does not cause respiratory depression; it reverses sedation.

17. Match the toxin with its antidote. Atropine and pralidoxime treat:

    1. A. Calcium channel blocker overdose
    2. B. Organophosphate poisoning
    3. C. Cyanide poisoning
    4. D. Iron poisoning
    Show answer

    Answer: B. Organophosphate poisoning

    Atropine blocks muscarinic effects and pralidoxime reactivates acetylcholinesterase. Calcium treats calcium channel blockers, hydroxocobalamin treats cyanide, and deferoxamine treats iron.

18. A 25-year-old in cardiac arrest from a calcium channel blocker overdose has had no ROSC after 20 minutes of ALS. Regarding the length of the resuscitation, the best guidance is that:

    1. A. Stop now, at the 20-minute mark
    2. B. Stop if the first rhythm was PEA
    3. C. Stop once calcium has been given
    4. D. Longer efforts may be reasonable
    Show answer

    Answer: D. Longer efforts may be reasonable

    AHA guidance on poisoning recognizes that patients in toxic cardiac arrest can survive neurologically intact after prolonged CPR, and that extracorporeal life support may be considered in refractory poisoning, so usual termination time limits should not be applied rigidly; contact medical control. A 20-minute cutoff comes from rules derived in typical cardiac arrests. PEA is common in drug-induced arrest and is not a reason to stop. Calcium is one treatment, not an endpoint.

19. A 22-year-old says he took an unknown number of pills. He is alert with normal vital signs. A 12-lead ECG is useful mainly because it can show:

    1. A. QRS or QT prolongation from the drug
    2. B. The amount of drug that was taken
    3. C. Whether the overdose was intentional
    4. D. The level of drug in the blood
    Show answer

    Answer: A. QRS or QT prolongation from the drug

    Many common drugs (tricyclics, antihistamines, antipsychotics, methadone, some antidepressants) widen the QRS or lengthen the QT before the patient looks ill, and those changes predict seizures and dysrhythmias. An ECG cannot measure the dose or blood level, and it cannot show intent; those come from the history and the lab.

20. Hydroxocobalamin reverses cyanide toxicity by:

    1. A. Speeding carbon monoxide removal
    2. B. Displacing oxygen from hemoglobin
    3. C. Binding cyanide to form cyanocobalamin
    4. D. Reactivating the cholinesterase enzyme
    Show answer

    Answer: C. Binding cyanide to form cyanocobalamin

    Hydroxocobalamin's cobalt binds cyanide to form cyanocobalamin (vitamin B12), which the kidneys excrete, freeing cytochrome oxidase to use oxygen again. It does not remove carbon monoxide; oxygen does that. It does not displace oxygen from hemoglobin, which would worsen hypoxia. Reactivating cholinesterase is the action of pralidoxime in organophosphate poisoning.

21. The old 'coma cocktail' gave dextrose, naloxone, thiamine, and flumazenil to every unresponsive patient. Current practice has replaced it with:

    1. A. Giving all four drugs at double doses
    2. B. Targeted treatment based on findings
    3. C. Flumazenil first, then the other three
    4. D. Withholding every drug until arrival
    Show answer

    Answer: B. Targeted treatment based on findings

    Each drug is now given for a reason: dextrose for a measured low glucose, naloxone for respiratory depression suggesting opioids, and thiamine with dextrose for the malnourished. Flumazenil is no longer given blindly because it can cause seizures in benzodiazepine-dependent or tricyclic patients. Withholding all treatment until the hospital would delay simple fixes such as dextrose.

22. Fomepizole treats toxic alcohol ingestion by:

    1. A. Binding the alcohol in the bloodstream for excretion
    2. B. Reversing the acidosis caused by the toxic metabolites
    3. C. Speeding the breakdown of the alcohol in the liver
    4. D. Blocking alcohol dehydrogenase so metabolites don't form
    Show answer

    Answer: D. Blocking alcohol dehydrogenase so metabolites don't form

    The parent alcohols are relatively harmless; their metabolites cause acidosis and organ damage. Fomepizole stops metabolism so the kidneys can clear the parent compound.

23. At a suspected nerve agent release, a decontaminated adult has severe difficulty breathing, copious secretions, muscle twitching, and confusion. Using DuoDote (atropine and pralidoxime) auto-injectors, you should give:

    1. A. One auto-injector, then wait a full hour
    2. B. One auto-injector pushed directly into a vein
    3. C. Three auto-injectors 15 minutes apart
    4. D. Three auto-injectors IM in rapid succession
    Show answer

    Answer: D. Three auto-injectors IM in rapid succession

    The DuoDote label directs three injections into the mid-lateral thigh in rapid succession for severe symptoms such as respiratory distress, heavy secretions, fasciculations, confusion, or seizures; one injection is given for mild symptoms, with two more if severe signs develop. A benzodiazepine is added for seizures, and further atropine is titrated to drying of secretions per medical direction. Waiting an hour or spacing doses 15 minutes apart delays reversal of the bronchorrhea and bronchospasm that kill these patients. The device is designed only for intramuscular use and cannot be given IV. (DuoDote FDA prescribing information; HHS CHEMM, nerve agents.)

24. When transporting a patient who has taken an unknown overdose, the most important ongoing monitoring includes:

    1. A. Visual acuity, pupil response, and skin turgor
    2. B. Temperature only, rechecked every 30 minutes
    3. C. Rhythm, SpO2, ETCO2, and repeated mental status
    4. D. Blood glucose only, rechecked every 5 minutes
    Show answer

    Answer: C. Rhythm, SpO2, ETCO2, and repeated mental status

    Many toxins cause dysrhythmias and hypoventilation, and capnography detects respiratory depression early. Glucose and temperature matter but are not enough alone.

25. Hemodialysis in the hospital is most useful for removing toxins such as:

    1. A. Lithium, salicylates, and toxic alcohols
    2. B. Tricyclic antidepressants and digoxin
    3. C. Benzodiazepines and opioids
    4. D. Calcium channel blockers and beta blockers
    Show answer

    Answer: A. Lithium, salicylates, and toxic alcohols

    Dialysis works for small, water-soluble drugs that are not highly protein bound. TCAs and digoxin are widely distributed in tissue, so dialysis removes little.