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10 free AEMT practice questions: Allergic Reaction and Anaphylaxis

These are real questions from the same bank the app draws from. Each one is written to the NREMT AEMT content specifications and kept inside the AEMT scope of practice. Pick an answer and you get the full rationale, including why the other three options are wrong.

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Question 1 of 10

A 38-year-old patient developed itching and a patch of raised red welts across both forearms about twenty minutes after weeding a garden. The voice is clear, speech comes in full sentences, the lung sounds are clear in all fields, and there is no swelling of the lips or tongue. The vital signs are BP 126/74, P 84, R 16, and SpO₂ 98% on room air. How should the AEMT classify this reaction?

Show the answer and rationale

Correct answer · A localized allergic reaction, since no other body system is involved

This is a localized allergic reaction. To sort an allergic reaction, ask whether the histamine has stayed in the skin or reached the airway or the circulation. This patient's voice is clear, speech comes in full sentences, the lungs are clear, and there is no swelling of the lips or tongue. The blood pressure is 126/74 and the pulse is 84. The skin is the only system involved. A localized reaction gets monitoring and transport, not epinephrine. Keep reassessing on the way in, because the reaction can still spread to another system later. Classify the reaction on what you see right now.

Why the others are wrong

Anaphylaxis, since hives cover more than one part of the body: Hives over more than one part of the body do look alarming. How much skin is involved does not decide anaphylaxis. A body covered in hives with nothing else involved is still one body system. One system is a localized reaction.

An anaphylactic reaction in its early stage, ahead of the airway signs: Calling this early anaphylaxis turns a classification into a guess about what comes next. Anaphylaxis needs a second body system involved, and this patient has only the skin. Treat the findings you actually have, and reassess for the ones you do not.

A biphasic reaction returning after an exposure earlier in the day: A biphasic reaction is symptoms coming back hours after a reaction that was already treated. This patient has had one reaction, and the reaction has not gone away and come back. What you are seeing is still the first reaction.

Question 2 of 10

A 79-year-old patient with coronary artery disease and two prior stents has hives, swelling of the lips, and audible wheezing about eight minutes after a wasp sting. A crew member says epinephrine could strain this heart and suggests oxygen, an antihistamine, and a fast trip instead. The vital signs are BP 94/56, P 118, R 24, and SpO₂ 93% on room air. Which action should the AEMT take?

Show the answer and rationale

Correct answer · Give epinephrine into the thigh muscle and monitor the heart closely

This patient is in anaphylaxis, with hives, swollen lips, and audible wheezing eight minutes after a wasp sting. The crew member is right that epinephrine raises the heart rate, the blood pressure, and how much oxygen the heart muscle needs. In a patient with coronary disease, that extra work is a real cost. Epinephrine still has no absolute contraindication in true anaphylaxis. The reaction is already stressing this heart, with a blood pressure of 94/56 and a pulse of 118. A cardiac history changes what you watch after the drug, not whether you give it. Give epinephrine into the thigh muscle, then watch the heart rhythm and the chest closely.

Why the others are wrong

Give the antihistamine now and hold epinephrine for a falling pressure: Holding epinephrine until the pressure falls sounds careful for a heart patient. The pressure is already low at 94/56, and the airway is already involved. Holding the drug lets a reaction you can treat keep stressing the heart.

Give a nebulized bronchodilator, which carries less cardiac risk here: A bronchodilator opens the lower airways and seems gentler on a heart patient. Albuterol also raises the heart rate, so albuterol is not gentler on the heart. A bronchodilator also does nothing for the lip swelling or the dilated blood vessels.

Establish a line and give fluid, then reassess before any epinephrine: Fluid is part of anaphylaxis care, and fluid does not stress the coronary arteries. Fluid cannot shrink dilated blood vessels. The pressure keeps sliding down while you lose the minutes when epinephrine works best.

Question 3 of 10

A 60-year-old patient in anaphylaxis after eating shellfish received epinephrine into the thigh muscle, high-concentration oxygen, and airway support. The throat tightness has resolved and the wheezing has eased, but the patient is still pale and weak. An intravenous line is in place. The vital signs are BP 82/54, P 124, R 22, and SpO₂ 96% on oxygen. Which action should the AEMT take?

Show the answer and rationale

Correct answer · Give an isotonic crystalloid bolus through the line and reassess

This patient is still in distributive shock from anaphylaxis. Anaphylaxis makes the blood vessels widen and then leak. The throat tightness has resolved and the wheezing has eased, but the blood pressure is still 82/54 and the pulse is 124. The patient is still pale and weak. Epinephrine tightens the vessels back down, and that's why it comes first. The drug does not replace the plasma that has already leaked into the tissue. When the pressure stays low after intramuscular epinephrine and airway management, the next step at your level is a bolus of isotonic crystalloid. Give the bolus through the line and reassess. The vessels are now closer to their normal size, so the fluid does more now than it would have before the epinephrine.

Why the others are wrong

Give a nebulized bronchodilator to finish clearing the lower airways: A bronchodilator is in your scope and can treat a leftover wheeze. The wheezing here has already eased. The number that has not moved is the blood pressure. A bronchodilator treats the part of the patient that is getting better.

Place the patient on the side and recheck the pressure in five minutes: Placing the patient on the side and rechecking in five minutes is safe and costs nothing. A systolic pressure of 82 with a pulse of 124 after epinephrine means this patient needs volume now. Another five minutes of watching does not give the patient any volume.

Hold further treatment, since the airway findings have already cleared: The airway clearing up means the most dangerous half of the reaction has turned around. Perfusion is still failing. The vessels keep leaking volume out while you wait.

Question 4 of 10

A 25-year-old patient used a prescribed epinephrine auto-injector after a bee sting fifteen minutes ago. The hives have faded, the wheezing is gone, the patient feels completely well, and the question is why an ambulance ride is still necessary. The vital signs are BP 126/80, P 88, R 16, and SpO₂ 99% on room air. Which explanation should the AEMT give?

Show the answer and rationale

Correct answer · The symptoms can return hours later even without another exposure

Tell the patient the symptoms can come back hours later, even without another exposure. That second round is called a biphasic reaction. Epinephrine wears off on its own schedule, and the reaction does not follow that schedule. The histamine release can flare up again hours later even if the patient touches or eats nothing new. A biphasic reaction is the reason every anaphylaxis patient gets transported, including the ones who get much better. Right now the hives have faded, the wheezing is gone, and the vital signs are normal. Normal vital signs fifteen minutes after the auto-injector do not tell you the reaction is over.

Why the others are wrong

The epinephrine itself has to be watched for several hours afterward: Watching a patient after a strong drug sounds like standard care. The concern here is the reaction coming back, not the drug staying in the body. Epinephrine is short acting, so there is no reason to watch the drug itself for hours.

The sting site has to be checked for infection before the day is out: Sting sites can get infected, so a wound check is honest advice. Infection is not why this patient needs the ambulance. Giving that reason makes the trip sound routine and optional, and it gives the patient an easy reason to say no.

The blood pressure tends to drop once the swelling starts coming down: A falling blood pressure is the thing you worry about in anaphylaxis. Swelling going down is improvement. The blood pressure does not drop because the swelling comes down.

Question 5 of 10

A 72-year-old patient in anaphylaxis after a medication exposure has hives, swelling of the tongue, and wheezing. A family member hands the crew a bottle of oral antihistamine and asks whether that should be given while the crew sets up. Where do antihistamines belong in the treatment of anaphylaxis?

Show the answer and rationale

Correct answer · After epinephrine, as a hospital and advanced life support addition

Antihistamines come after epinephrine, as a hospital and advanced life support addition. Antihistamines and steroids are real anaphylaxis drugs, and they never come before epinephrine. An oral antihistamine takes far too long to work in a reaction that moves in minutes. An antihistamine does nothing for a tongue that is swelling or blood vessels that are already widened. This patient has hives, a swelling tongue, and wheezing. Epinephrine reverses both the swelling and the widened vessels right now. Give epinephrine first. The other drugs can come later at the hospital, with a physician there.

Why the others are wrong

Before epinephrine, since blocking histamine stops the whole cascade: Blocking histamine sounds like it should stop the whole reaction, and blocking histamine is how the drug works. The antihistamine only blocks receptors the histamine has not reached yet. The drug also arrives far too slowly to matter while the tongue is swelling.

Alongside epinephrine, so both drugs reach the tissue at the same time: In the hospital, patients often do get both drugs. On scene, setting up a second drug delays the first one. Epinephrine is the only drug here that reverses the reaction.

In place of epinephrine when the reaction is caught within ten minutes: Catching a reaction early does make the reaction easier to treat. Nothing takes the place of epinephrine at any point in the reaction. An early reaction is the one where epinephrine works best.

Question 6 of 10

Two patients are treated on the same shift for allergic reactions. One began having symptoms within two minutes of a sting, and the other began having symptoms about forty minutes after a meal. What does the speed of onset tell the AEMT about a reaction?

Show the answer and rationale

Correct answer · A faster onset tends to mean the reaction will be more severe

A faster onset tends to mean a more severe reaction. One patient started having symptoms within two minutes of a sting. The other started about forty minutes after a meal. Most allergic reactions start within minutes of the exposure. How fast a reaction starts is a rough measure of how severe the reaction will be. A fast start means more histamine is reaching more tissue in less time. The reaction has less time before it reaches the airway and the circulation. A slow reaction is not automatically safe, and onset speed does not tell you how the call will end. The patient whose symptoms started two minutes after the sting is the one you get set up for first and watch more closely.

Why the others are wrong

Onset speed reflects the amount of allergen rather than the severity: The amount of allergen does matter, because a bigger dose usually means a bigger effect. Onset speed is used to judge severity, not how much allergen got in. A tiny exposure can still cause a very fast reaction.

A slower onset is more dangerous, since the reaction builds unnoticed: In a lot of medicine, the slow and quiet problems are the dangerous ones. Allergic reactions work the other way. The fast reaction is the one already releasing histamine into the tissue when you arrive.

Onset speed predicts which body system the reaction will involve first: Knowing which body system gets hit first would help on this call. Onset speed does not tell you whether the airway, the circulation, or the skin will be involved first.

Question 7 of 10

A 90-year-old patient in anaphylaxis after eating shrimp has just received epinephrine into the thigh muscle. The voice is hoarse and the face is visibly swelling. The vital signs are BP 106/64, P 112, R 22, and SpO₂ 93% on room air. Which action should the AEMT take next?

Show the answer and rationale

Correct answer · Give high-concentration oxygen and keep a BVM within reach

This patient's airway is on its way to closing from anaphylaxis. The voice is hoarse and the face is still swelling after the epinephrine. Epinephrine helps, but epinephrine does not undo swelling that is already in the tissue. Give high-concentration oxygen now, while the airway is still open. Keep the BVM and suction within reach, not in the bag. If the airway gets worse, you need the BVM in your hand right away.

Why the others are wrong

Set up a nebulized bronchodilator for the narrowing that is developing: A nebulized bronchodilator helps when bronchospasm is the problem, and a bronchodilator may be part of this call later. This patient's problem is a hoarse voice and a swelling face. That swelling sits above the vocal cords, where a nebulized drug cannot reach.

Establish a line and start an isotonic crystalloid bolus for the swelling: A fluid bolus is the next step when anaphylaxis stays hypotensive after epinephrine. This patient's pressure is holding at 106/64. Fluid also does nothing for tissue swelling. Starting a line now treats the wrong problem.

Lay the patient flat and recheck the pressure in about five minutes: Laying the patient flat and rechecking the pressure fits a patient who is still hypotensive. This patient's face and throat are swelling. Laying this patient flat makes the airway harder to manage when the airway needs the most room.

Question 8 of 10

An 88-year-old patient has hives, tongue swelling, and audible wheezing about ten minutes after a first dose of a new antibiotic. An intravenous line is already in place from an earlier transfer, and a crew member is reaching for the roller clamp to run fluid wide open. The vital signs are BP 76/44, P 130, R 24, and SpO₂ 92% on room air. Which action should the AEMT take?

Show the answer and rationale

Correct answer · Give epinephrine into the thigh muscle first, then address the volume

This patient is in anaphylaxis from the new antibiotic. There are hives, tongue swelling, and wheezing, and the blood pressure is 76/44 with a pulse of 130. The low pressure is real and fluid is part of this call, but the epinephrine has to come first. Anaphylaxis is a distributive shock. Histamine opens up the blood vessels and makes them leak fluid into the tissue. The patient has not lost blood. Pouring saline into vessels that keep getting wider and leakier does very little. Epinephrine tightens the vessels and stops the leak. Give the epinephrine into the thigh first. If the pressure stays low after the epinephrine, an isotonic crystalloid bolus is what you give next.

Why the others are wrong

Run the fluid wide open, since the vessels have lost their volume: Running fluid wide open fits a patient who has lost volume. This patient has not lost volume. The fluid moved out of the vessels and into the tissue through leaking vessel walls. Fluid alone keeps leaking out the same way until epinephrine stops the leak.

Give an antihistamine through the line to stop the histamine effect: An antihistamine goes after the histamine behind the reaction, and the line makes the drug easy to give. Antihistamines are hospital and advanced life support additions. Antihistamines never come before epinephrine. Epinephrine is the drug that tightens the vessels and stops the leak.

Raise the legs and recheck the pressure before committing to a drug: Rechecking the pressure fits a patient when you are not sure the low reading is real. This patient already has hives, tongue swelling, wheezing, and a pressure of 76/44. A recheck will not tell you anything new about this patient. Stopping to raise the legs and recheck only delays the epinephrine. Raising the legs is also no longer recommended as a treatment for shock.

Question 9 of 10

An AEMT cannot tell whether a wheezing patient is having an asthma attack or an anaphylactic reaction, and the guidance is to treat as anaphylaxis when the call is genuinely too close to make. Why is that the safer error?

Show the answer and rationale

Correct answer · Epinephrine also helps an asthmatic, while a bronchodilator misses swelling

Epinephrine still helps an asthmatic, and a bronchodilator misses the swelling of anaphylaxis. Say you give intramuscular epinephrine to a patient who turns out to have asthma. The epinephrine also improves the bronchospasm, and the asthmatic still gets better. Now say you give albuterol to a patient who turns out to have anaphylaxis. The albuterol treats the least dangerous part of the problem while the airway keeps closing. The two mistakes do not cost the patient the same amount. When you genuinely cannot tell, give the epinephrine, because epinephrine helps the patient either way.

Why the others are wrong

Epinephrine and a bronchodilator reach the narrowed airway equally fast: Both drugs do work quickly, so speed sounds like the thing to compare. Speed is not what separates them. A bronchodilator never reaches swollen tissue above the vocal cords, no matter how fast it works.

Anaphylaxis is far more common than asthma among adults who wheeze: Picking the more common condition is usually good reasoning in a close call. Asthma is far more common than anaphylaxis in people who wheeze, so option B has the numbers backwards. The reason to treat as anaphylaxis is what each mistake costs, not how often each condition happens.

A bronchodilator cannot be given once epinephrine is already on board: Nothing stops you from giving a bronchodilator after epinephrine. Giving a bronchodilator after epinephrine is common once the reaction is treated and the wheeze is still there.

Question 10 of 10

A 17-year-old patient ate shellfish at a family dinner about twelve minutes ago and now has hives across the trunk, has vomited twice, and reports cramping abdominal pain. The voice is clear, the lungs are clear, and the patient speaks in full sentences. The vital signs are BP 116/72, P 104, R 18, and SpO₂ 98% on room air. How should the AEMT classify this presentation?

Show the answer and rationale

Correct answer · Anaphylaxis, because two body systems are involved at the same time

This is anaphylaxis, because two body systems are involved at the same time. The hives across the trunk are the skin. The vomiting and cramping abdominal pain are the gut. Cramping, vomiting, or diarrhea all count as a second system. Skin plus gut meets the definition of anaphylaxis, even with a clear voice, clear lungs, and a normal blood pressure. Do not wait for the blood pressure to drop before you call this anaphylaxis. Waiting for low blood pressure is the mistake that hurts patients. The symptoms started twelve minutes after the shellfish. Treat this patient for anaphylaxis right now.

Why the others are wrong

A localized allergic reaction, since breathing and pressure are normal: Normal breathing and a normal pressure are reassuring. A localized reaction stays in one place and one system. This reaction has already reached the skin and the gut at the same time.

Food poisoning, since vomiting and cramping came on after a meal: Vomiting and cramping after a meal fits food poisoning. Food poisoning takes hours, not twelve minutes. Food poisoning also does not cause hives, and the timing points to an allergen in the shellfish.

A biphasic reaction that will declare itself over the next few hours: A biphasic reaction is symptoms coming back after treatment seemed to work. This patient may still have a biphasic reaction later. This reaction is the first one, and it is happening now.

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