Allergy

On this page

Basics

• Summary
• Start Here
• Latest News
• Diagnosis and Tests
• Prevention and Risk Factors
• Treatments and Therapies

Learn More

• Related Issues
• Specifics
• Genetics

See, Play and Learn

• Health Check Tools
• Videos and Tutorials

Research

• Statistics and Research
• Clinical Trials
• Journal Articles

Resources

• Reference Desk
• Find an Expert

For You

• Children
• Teenagers
• Patient Handouts

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.

NIH: National Institute of Allergy and Infectious Diseases

Start Here

• Allergic Reactions (American Academy of Allergy, Asthma, and Immunology) Also in Spanish

Latest News

• What's the Best Seasonal Allergy Med for Your Kid? (04/17/2017, HealthDay)
• Mite-Proof Bedding May Help Curb Asthma Attacks (03/10/2017, HealthDay)
• Daffodils, Margaritas and Other Surprise Skin Dangers (03/03/2017, HealthDay)
• More News on Allergy

Diagnosis and Tests

• Allergy Blood Testing (American Association for Clinical Chemistry)
• Allergy Skin Tests (Mayo Foundation for Medical Education and Research)
• Allergy Testing (American Academy of Allergy, Asthma, and Immunology) Also in Spanish
• Allergy Tests: When You Need Them and When You Don't (ABIM Foundation)
• Cold or Allergies: Which Is It? (For Parents) (Nemours Foundation)
• Cold, Flu, or Allergy? Know the Difference for Best Treatment (National Institutes of Health) Also in Spanish
• WBC (White Blood Cell) Differential Count (American Association for Clinical Chemistry)

Prevention and Risk Factors

• Allergens and Irritants (National Institute of Environmental Health Sciences)
• Allergy-Proof Your House (Mayo Foundation for Medical Education and Research)
• Environmental Control Measures (For Parents) (Nemours Foundation)
• Trigger Avoidance in Allergic Rhinitis (Beyond the Basics) (UpToDate)

Treatments and Therapies

• Allergy Medications: Know Your Options (Mayo Foundation for Medical Education and Research)
• Allergy Shots: Could They Help Your Allergies? (American Academy of Family Physicians) Also in Spanish
• Butterbur (National Center for Complementary and Integrative Health)
• Decongestants: OTC Relief for Congestion (American Academy of Family Physicians) Also in Spanish
• Itching for Allergy Relief? (Food and Drug Administration)
• Medicines to Treat Allergies (Consumers Union of U.S., National Center for Farmworker Health) - PDF Also in Spanish
• Nasal Wash Treatment (National Jewish Health) Also in Spanish
• Time to Talk: 5 Things to Know about Complementary Health Approaches for Seasonal Allergy Relief (National Center for Complementary and Integrative Health)
• Treating Allergies, Hay Fever, and Hives (Consumers Union of U.S.) - PDF Also in Spanish

Related Issues

• 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)
• Allergy Capitals (Asthma and Allergy Foundation of America)
• Allergy Meds Could Affect Your Driving (Food and Drug Administration) Also in Spanish
• Colds, Allergies and Sinusitis - How to Tell the Difference (American Academy of Allergy, Asthma, and Immunology) - PDF Also in Spanish
• Eosinophilic Esophagitis (EE) or (EoE) (American Academy of Allergy, Asthma, and Immunology) Also in Spanish
• Feel Better. Live Better. See an Allergist / Immunologist (American Academy of Allergy, Asthma, and Immunology) Also in Spanish

Specifics

• Allergic Skin Conditions (American Academy of Allergy, Asthma, and Immunology) Also in Spanish
• Cockroach Allergy (Asthma and Allergy Foundation of America)
• Dust Mite Allergy (Mayo Foundation for Medical Education and Research)
• Mold Allergy (Asthma and Allergy Foundation of America)
• Nickel Allergy (Mayo Foundation for Medical Education and Research)
• Oral Hypersensitivity Reactions (American Association of Oral and Maxillofacial Surgeons)
• Pet Allergy (Mayo Foundation for Medical Education and Research)
• 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)

Genetics

• Genetics Home Reference: allergic asthma (National Library of Medicine)
• Genetics Home Reference: atopic dermatitis (National Library of Medicine)
• Genetics Home Reference: Netherton syndrome (National Library of Medicine)
• Genetics Home Reference: vibratory urticaria (National Library of Medicine)

Health Check Tools

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

Videos and Tutorials

• Allergies (Medical Encyclopedia) Also in Spanish
• Virtual Allergist (American Academy of Allergy, Asthma, and Immunology)

Statistics and Research

• FastStats: Allergies/Hay Fever (National Center for Health Statistics)
• Prevalence of Allergies the Same, Regardless of Where You Live (National Institute of Environmental Health Sciences)
• Seasonal Allergies at a Glance: What the Science Says (National Center for Complementary and Integrative Health)
• Trends in Allergic Conditions among Children: United States, 1997-2011 (National Center for Health Statistics)

Clinical Trials

• ClinicalTrials.gov: Hypersensitivity (National Institutes of Health)
• ClinicalTrials.gov: Rhinitis, Allergic, Perennial (National Institutes of Health)

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

• Article: Inhalant Allergens in Portugal.
• Article: Japanese guidelines for occupational allergic diseases 2017.
• Article: CpG oligodeoxynucleotide nanomedicines for the prophylaxis or treatment of cancers,...
• Allergy -- see more articles

Reference Desk

• Allergy and Asthma Health Magazine (American Association for Respiratory Care)
• Overview of the Immune System (National Institute of Allergy and Infectious Diseases)

Find an Expert

• American Academy of Allergy, Asthma, and Immunology
• Find an Allergist/Immunologist (American Academy of Allergy, Asthma, and Immunology)
• National Institute of Allergy and Infectious Diseases
• National Institute of Environmental Health Sciences Also in Spanish

Children

• All about Allergies (For Parents) (Nemours Foundation) Also in Spanish
• Allergy Relief for Your Child (Food and Drug Administration) Also in Spanish
• Allergy Shots (For Parents) (Nemours Foundation) Also in Spanish
• Do Allergies Cause Asthma? (Nemours Foundation) Also in Spanish
• Learning about Allergies (Nemours Foundation) Also in Spanish
• Prevention of Allergies and Asthma in Children (American Academy of Allergy, Asthma, and Immunology) Also in Spanish
• What Is a Pediatric Allergist / Immunologist? (American Academy of Pediatrics) Also in Spanish

Teenagers

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

Patient Handouts

• 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