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A 47-year-old member asked about a member:

What is the worst thing that could happen due to an allergic reaction?

18 doctor answers47 doctors weighed in
Dr. Alan Greene
Dr. Alan Greeneanswered
Pediatrics 35 years experience
Anaphylaxis: The most severe reaction that can occur after repeated exposure to something you are allergic to is called anaphylaxis. This rare but sudden condition causes itchy welts (hives), followed by wheezing, shortness of breath, and occasionally, swelling of the tongue or throat. Without treatment, swelling of the tongue or throat can sometimes worsen and block the airway.
Dr. Joel Selter
Dr. Joel Selter commented
Pediatrics - Allergy & Asthma 38 years experience
While anaphylaxis is the most common immediate life threatening hypersensitivity reaction- oftentime to foods, one should be alert to some of the very severe reactions associated with drug hypersensitivity- such as Stevens Johnson, Toxic Epidermal Necrolyis (TEN) as well as DRESS.
Jan 17, 2012
Dr. Gregg Alexander
Pediatrics 34 years experience
Unable to breath: A full blown allergic reaction (anaphylaxis) could lead to swelling of the throat and a closed air passage. Breathing is pretty much the most important thing we do, so having the ability to move air in and out is essential!
Dr. Pamela Lindor
Pediatrics 33 years experience
Anaphylaxis: A true, severe allergic reaction can be life threatening. An allergen can trigger what is called an anaphylactic reaction, causing rash, wheezing, low blood pressure and other serious symptoms. Most "allergies" however, are much less severe. If you have concerns about possible allergies in your child, ask your pediatrician.
Dr. Robert Kwok
Pediatrics 34 years experience
Unfortunately, death: In rare cases, allergic reactions can be fatal. This may happen if the tongue or throat swells up and blocks off one's breathing. Death may also occur if the allergic reaction drops the blood pressure too low for too long, destroys the majority of one's blood cells or platelets, or severely damages the skin all over the body (mimicking a large burn).
Dr. Paul Trani
Specializes in Pediatrics
Anaphylaxis: Anaphylaxis is the most severe type of allergic reaction. It results in swelling of areas within the mouth, throat, and upper airways, which can cause severe difficulty in breathing. Anaphylaxis can also have GI complications as well. Doctors give Epinephrine to families where anaphylaxis is a risk. These are commonly called 'epi-pens'.
Dr. Jay Park
Dr. Jay Parkanswered
Pediatrics 51 years experience
Shock and death: The most severe allergic reaction, so called anaphylaxis, involve shortness of breath/wheezing, hypotension, urticarial rash (hives), and swelling of vocal cords. Anaphylactic reaction can be deadly if an appropriate treatment is not rendered in time. Peanut and bee venom allergy are good examples.
Dr. Kevin Windisch
Pediatrics 26 years experience
Anaphylaxis: The worst thing that could happen is that your airway could swell shut, you could stop breathing and your heart stop. This is why people with severe allergies need to carry an Epinephrine pen with them at all times.
Dr. Jeffrey Min
Specializes in Pediatrics
Anaphylaxis/death: In severe cases of allergic reactions, a person can develop anaphylaxis which can include tightening of the airways/throat to cause problems breathing and sometimes even stop breathing. It can also lead to a drop in blood pressure/shock which can lead to death.
Dr. Arthur Torre
Pediatric Allergy and Asthma 52 years experience
Anaphylaxis: The worse allergic reaction which typically occurs to severe food allergy is anaphylaxis is defined as "a serious allergic reaction that is rapid in onset and may cause death". Symptoms may include hives or swollen lips, difficulty breathing and reduced blood pressure leading to shock.
Dr. Victoria Acharya
Specializes in Pediatrics
Anaphylaxis: Anaphylaxis is very dangerous, because the airway can swell up and close off. Anyone with a history of a severe food allergy (mouth or lip swelling) should have two epinephine ("epi") pens with him/her at all times. There are also blood tests that can help predict which foods or exposures could trigger a severe allergic reaction.
Dr. Andrew Murphy
Allergy and Immunology 30 years experience
Death: The worst thing that happen from an allergic reaction is death. This most serious allergic reaction is called anaphylaxis and can occur after exposure to certain foods, bees sting reaction, medication reactions or other unusual causes.
Dr. Timothy King
21 years experience
You could die: In severe allergic reactions you develop anaphylaxis which causes a massive histamine release, your throat swells closed and you blood pressure can drop. Without immediate intervention, you cannot breath and die.
Dr. Jason Campbell
Family Medicine 17 years experience
Anaphylaxis: The absolute worst thing that could happen with an allergic reaction would be anaphylaxis resulting in respiratory compromise such as a swollen throat or tongue obstructing the airway and can possibly result in death.
Dr. Kevin Windisch
Pediatrics 26 years experience
Death: Your lips, tongue and airways (large and small) could all swell shut. At the same time your blood pressure could drop, this is called anaphylaxis.
Dr. Alan Khadavi
Allergy and Immunology 23 years experience
Then you could die too.
Jan 17, 2012
Dr. Maziar Rezvani
Allergy and Immunology 22 years experience
Death: Which is usually secondary to hypotension or asphyxiation. Less commonly hypoxemia from severe bronchospasm can also occur.
Dr. Alan Khadavi
Allergy and Immunology 23 years experience
You die.: Hypotension, shock, or closing of the throat.
Dr. Pedro Hernandez
Geriatrics 41 years experience
Death: People with serious allergies must carry with them Epinephrine injectable (epipen)for just in case of emergency.
Dr. Bhavin Patel
Allergy and Immunology 26 years experience
DEATH: Symptoms from an allergic reaction can range from an annoying symptoms such as itch or irritation to death.

Similar questions

A 45-year-old member asked:

What can happen if i don't do anything about an allergic reaction?

1 doctor answer1 doctor weighed in
Dr. John Chiu
Allergy and Immunology 58 years experience
Depends: If the reactions are from an acute exposure, one may expect subsidence in symptoms after a few hours. If the reaction is from daily exposure, then your quality of life will likely be adversely affected. If you have allergic asthma, you may end up in the hospital or worse if it goes untreated. If you have an anaphylactic reaction, you may die from it. The outcome depends on the severity .
Last updated Dec 29, 2019


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