Allergic Reactions Definition

Allergic Reactions: Definition

Allergic reactions tend to be more common occurrences than you may otherwise believe, because allergic reactions definition encompasses everything from a sty in the eye to life-threatening anaphylactic shock.

Once an allergen makes its way into your body, defense mechanisms begin a chain of reaction. These defense mechanisms trigger a safety antibody known as immunoglobulin E (IgE) to battle entering substances. Despite the fact that everybody has IgE within their body, individuals with allergic reaction have an abnormally large amount.

This army of antibodies begins an attack on not only the allergic substance; they can also injure mast cells. When these cells are injured they become inflamed. In response to the inflammation they release histamine, which is what you experience as an allergic attack.

Hypersensitive Reaction and Antigens

Put another way, a hypersensitive reaction is the body's method of reacting to some perceived “enemy” or foreign substances known as antigens. Made of protein, these antigens will trigger the body's life-saving defense mechanisms. People experiencing allergic responses will find themselves escalating into a hypersensitivity reaction, meaning their response is far above what's necessary to be able to safeguard against a specific antigen.

So many things can be considered an allergen:  dog-cat

  • dust
  • pollen
  • medication
  • latex
  • plants
  • insect venom
  • animal dander
  • infections
  • bacteria
  • foods like peanuts, shellfish, strawberries, eggs, etc.

Individual responses vary, from a small skin rash and scratchy eyes to a body rash or difficulty breathing. Their response may also include multiple signs and symptoms. Allergic reactions are extremely common and account in excess of 17 million doctors visits annually. Over fifty percent of those visits are for chronic allergic reactions.

How Do Allergic Reactions Evolve?

A hypersensitive reaction might not happen the very first time you are exposed. For instance, the first time you are stung by a bee you may have only discomfort and redness. But your body has been exposed to this specific allergen and if you have an overactive response, the next time you encounter the same allergen, you might have hives or even a constricted airway. Your defense mechanisms now respond in a hyperactive method to that allergen.

Allergic reactions can also occur along with other illnesses like bronchial asthma, ear infections, sleep apnea and sinus problems.



Anaphylaxis is a life- threatening type of allergic responses that affects several parts of the body at one time. Severe anaphylaxis is frequently fatal unless the person gets emergency care immediately.

Anaphylaxis is triggered by substances which are either injected or consumed but get access to the blood stream. It's highly improbable for somebody with an anaphylactic response to an allergen that is simply breathed in, but it has happened.


Because allergic responses can progress and worsen, medical assistance is suggested for anything besides the most minor and localized signs and symptoms. However, if these signs and symptoms continue over a couple of days, or they do not get better using the suggested treatment methods, it's also wise to talk to your doctor.

Any responses to medications, that fall under the heading of drug allergic reactions, need to be reported for your physician so medicines within this same category won't be prescribed again.

For typical reactions, your healthcare provider is going to do an intensive health background and physical examination. Blood tests and x-rays or any other imaging tests are not essential unless there are very unusual conditions.

People who are allergic need to avoid their triggers since with repeated exposure the allergic attack could possibly get considerably worse. For instance, somebody who has a latex susceptibility can improve their response to a full-blown allergy if they are consistently exposed to latex.

Home remedies are not enough if you are struggling with a serious reaction in your own home. Go immediately to an emergency room. If nobody is available immediately call an ambulance for emergency medical transport. Don't attempt driving yourself under any circumstances.

If you have had an epinephrine auto-injector prescribed, inject it. It could also be wise to take an oral dose of antihistamine. When you are admitted to the ER, doctors will start treatment with antihistamines and adrenal cortical steroids to reverse the histaminic response in your body.

You might find that you need to remain in a healthcare facility from a few hours to a few days to be able to be fully treated.

Going forward, you need to identify and record any allergic response which you might have and report this to your doctor.  Don't hold back until your allergic attack becomes life-threatening.

Also, wearing an allergy bracelet along with carrying an epi-pen (epinephrine injection) could save your life.


MedlinePlus: Allergic Responses

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American Academy of Allergy, Bronchial asthma and Immunology: Allergic Responses: Ideas to Remember

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College of Maryland Clinic: Allergic Responses

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National Institute of Allergy and Infectious Disease: Food Hypersensitivity

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Children and Allergic Reactions Serious Allergic Responses

Northwestern College: Youngsters with Food Allergic Reactions Can Fall With the Cracks

http://world wide reactions-fall-through-cracks.html