Immunology

Are microbes causing your milk allergy?

In the past 30 years, food allergies have become increasingly common in the United States. Changes to human genetics can't explain the sudden rise. That is because it takes many generations for changes to spread that widely ...

Pediatrics

Breastmilk sugars differ in pregnant women on probiotics

The complex sugars found in human breastmilk, long believed to be fixed in their composition, may change in women who are taking probiotics, according to new research from the University of Rochester Medical Center (URMC).

Diseases, Conditions, Syndromes

Human respiratory viruses continue to spread in wild chimpanzees

Less than two years after the first report of wild chimpanzees in Uganda dying as a result of a human "common cold" virus, a new study has identified two other respiratory viruses of human origin in chimpanzee groups in the ...

Immunology

Study finds unique form of chronic sinusitis in older patients

Older patients with a diagnosis of chronic sinusitis—a disease of the nasal cavity and paranasal sinuses that often persists over many years—have a unique inflammatory signature that may render them less responsive to ...

Immunology

Asthma medications: Know your options

Confused about your asthma medications? Here's what you need to know to sort out the main classes and numerous subtypes of asthma drugs.

Diseases, Conditions, Syndromes

Home remedies: Healthy use of humidifiers

Humidifiers can ease problems caused by dry air. Dry sinuses, bloody noses and cracked lips—humidifiers can help soothe these familiar problems caused by dry indoor air. Humidifiers can also help ease symptoms of a cold ...

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An allergy is a hypersensitivity disorder of the immune system. Allergic reactions occur when a person's immune system reacts to normally harmless substances in the environment. A substance that causes a reaction is called an allergen. These reactions are acquired, predictable, and rapid. Allergy is one of four forms of hypersensitivity and is formally called type I (or immediate) hypersensitivity. Allergic reactions are distinctive because of excessive activation of certain white blood cells called mast cells and basophils by a type of antibody called Immunoglobulin E (IgE). This reaction results in an inflammatory response which can range from uncomfortable to dangerous.

Mild allergies like hay fever are very common in the human population and cause symptoms such as red eyes, itchiness, and runny nose, eczema, hives, hay fever, or an asthma attack. Allergies can play a major role in conditions such as asthma. In some people, severe allergies to environmental or dietary allergens or to medication may result in life-threatening reactions called anaphylaxis. Food allergies, and reactions to the venom of stinging insects such as wasps and bees are often associated with these severe reactions.

A variety of tests exist to diagnose allergic conditions. These include placing possible allergens on the skin and looking for a reaction such as swelling. Blood tests can also be done to look for an allergen-specific IgE.

Treatments for allergies include avoiding known allergens, use of medications such as anti-histamines that specifically prevent allergic reactions, steroids that modify the immune system in general, and medications such as decongestants that reduce the symptoms. Many of these medications are taken by mouth, though epinephrine, which is used to treat anaphylactic reactions, is injected. Immunotherapy uses injected allergens to desensitize the body's response.

This text uses material from Wikipedia licensed under CC BY-SA