Allergic reactions

Definition of Allergic reactions

Allergic reactions are sensitivities to substances, called allergens, that come into contact with the skin, nose, eyes, respiratory tract, and gastrointestinal tract. They can be inhaled into the lungs, swallowed, or injected.


Common symptoms of a mild allergic reaction include:


David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Stuart I. Henochowicz, MD, FACP, Associate Clinical Professor of Medicine, Division of Allergy, Immunology, and Rheumatology, Georgetown University Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 5/2/2010

Allergic reactions
Dermatographism - close-up
Dermatographism on the arm
Hives (urticaria) on the arm
Hives (urticaria) on the chest
Hives (urticaria) - close-up
Hives (urticaria) on the trunk
Dermatographism on the back
Dermatographism - arm
Allergic reactions

ADAM Medical Encyclopedia

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