Allergy (original) (raw)

Also called: Hypersensitivity

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Summary

An allergy is a reaction by your immune system to something that does not bother most other people. People who have allergies often are sensitive to more than one thing. Substances that often cause reactions are:

• Pollen
• Dust mites
• Mold spores
• Pet dander
• Food
• Insect stings
• Medicines

Normally, your immune system fights germs. It is your body's defense system. In most allergic reactions, however, it is responding to a false alarm. Genes and the environment probably both play a role.

Allergies can cause a variety of symptoms such as a runny nose, sneezing, itching, rashes, swelling, or asthma. Allergies can range from minor to severe. Anaphylaxis is a severe reaction that can be life-threatening. Doctors use skin and blood tests to diagnose allergies. Treatments include medicines, allergy shots, and avoiding the substances that cause the reactions.

• Allergens and Irritants (National Institute of Environmental Health Sciences)

• Allergy-Proof Your House (Mayo Foundation for Medical Education and Research) Also in Spanish

• Allergic Bronchopulmonary Aspergillosis (ABPA) (American Academy of Allergy, Asthma, and Immunology) Also in Spanish

• Allergies and Asthma: They Often Occur Together (Mayo Foundation for Medical Education and Research)

• Colds, Allergies and Sinusitis - How to Tell the Difference (American Academy of Allergy, Asthma, and Immunology) - PDF Also in Spanish

• Eosinophilic Esophagitis: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish

• Feel Better. Live Better. See an Allergist / Immunologist (American Academy of Allergy, Asthma, and Immunology) Also in Spanish

• Is It Flu, COVID-19, Allergies, or a Cold? (National Institutes of Health) Also in Spanish

• Marvels of Mucus and Phlegm: The Slime That Keeps You Healthy (National Institutes of Health) Also in Spanish

• Allergic Skin Conditions (American Academy of Allergy, Asthma, and Immunology)

• Cockroach Allergy (Asthma and Allergy Foundation of America)

• Dust Mite Allergy (Mayo Foundation for Medical Education and Research) Also in Spanish

• Mold Allergy (Asthma and Allergy Foundation of America)

• Nickel Allergy (Mayo Foundation for Medical Education and Research) Also in Spanish

• Oral Hypersensitivity Reactions (American Association of Oral and Maxillofacial Surgeons)

• Pet Allergy (Mayo Foundation for Medical Education and Research) Also in Spanish

• Physical Allergy (Merck & Co., Inc.) Also in Spanish

• Stinging Insect Allergy (American Academy of Allergy, Asthma, and Immunology) Also in Spanish

• Sun Allergy (Mayo Foundation for Medical Education and Research) Also in Spanish

• Pet Allergy Quiz (American Academy of Allergy, Asthma, and Immunology)

• Seasonal Allergy Quiz (Medical Encyclopedia) Also in Spanish

• Overview of the Immune System (National Institute of Allergy and Infectious Diseases)

• Allergies (Nemours Foundation)

• Do Allergies Cause Asthma? (Nemours Foundation) Also in Spanish

• Allergic reactions (Medical Encyclopedia) Also in Spanish

• Allergic rhinitis - self-care (Medical Encyclopedia) Also in Spanish

• Allergies (Medical Encyclopedia) Also in Spanish

• Allergies, asthma, and dust (Medical Encyclopedia) Also in Spanish

• Allergies, asthma, and molds (Medical Encyclopedia) Also in Spanish

• Allergy testing - skin (Medical Encyclopedia) Also in Spanish

• Angioedema (Medical Encyclopedia) Also in Spanish

• Antihistamines for allergies (Medical Encyclopedia) Also in Spanish