9 doctors weighed in:

What is an allergy?

9 doctors weighed in
Dr. Alan Goldsobel
Internal Medicine - Allergy & Immunology
6 doctors agree

In brief: Abnormal reaction

An allergy is an abnormal, incorrect reaction of the immune system against substances we are exposed to in our environment.
This includes environmental exposures, foods, drugs, etc. Allergies must be differentiated from other reactions not mediated specifically through the immune system including irritants, intolerance, etc. In general, allergy involves the respiratory tract, skin, or GI system.

In brief: Abnormal reaction

An allergy is an abnormal, incorrect reaction of the immune system against substances we are exposed to in our environment.
This includes environmental exposures, foods, drugs, etc. Allergies must be differentiated from other reactions not mediated specifically through the immune system including irritants, intolerance, etc. In general, allergy involves the respiratory tract, skin, or GI system.
Dr. Alan Goldsobel
Dr. Alan Goldsobel
Thank
Dr. Steven Machtinger
Internal Medicine - Allergy & Immunology
1 doctor agrees

In brief: Immune Over-reaction

Allergy is like the dog biting the mailman.
Dogs are supposed to welcome friends & attack foes. When the immune system (dog) mistakes a harmless substance (like food) for a dangerous one (like an infection) the over-reaction results in symptoms we call allergy. When the immune system needlessly attacks parts of our own body the result is autoimmune disease. Harder question - why does this happen?

In brief: Immune Over-reaction

Allergy is like the dog biting the mailman.
Dogs are supposed to welcome friends & attack foes. When the immune system (dog) mistakes a harmless substance (like food) for a dangerous one (like an infection) the over-reaction results in symptoms we call allergy. When the immune system needlessly attacks parts of our own body the result is autoimmune disease. Harder question - why does this happen?
Dr. Steven Machtinger
Dr. Steven Machtinger
Thank
Dr. Yoram Padeh
Internal Medicine - Allergy & Immunology

In brief: Misdirected response

An allergy is an abnormal response by a component of the immune system to certain foreign proteins encountered by the body.
These proteins are generally not harmful (e.g. Foods, pollen) but for reasons which are yet unclear, trigger a response by this component of the immune system which under "normal" circumstances should only target parasites. This immune reaction then causes allergy symptoms.

In brief: Misdirected response

An allergy is an abnormal response by a component of the immune system to certain foreign proteins encountered by the body.
These proteins are generally not harmful (e.g. Foods, pollen) but for reasons which are yet unclear, trigger a response by this component of the immune system which under "normal" circumstances should only target parasites. This immune reaction then causes allergy symptoms.
Dr. Yoram Padeh
Dr. Yoram Padeh
Thank
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