Allergy
Introduction
An allergy is a hypersensitive reaction of the immune system to certain substances, known as allergens, that are harmless for most people. These allergens can be found in dust mites, pet dander, pollen, insects, ticks, molds, foods and some medicines. When a person is allergic to a substance, the immune system mistakenly believes that this usually harmless substance is actually harmful to the body.
Immune Response in Allergy
In an allergic reaction, the immune system responds to an allergen by releasing proteins called IgE antibodies. These antibodies travel to cells that release chemicals, causing an allergic reaction. This reaction usually causes symptoms in the nose, lungs, throat, sinuses, ears, lining of the stomach or on the skin.
Types of Allergies
There are several types of allergies, including:
- Food allergies
- Drug allergies
- Insect allergies
- Latex allergies
- Mold allergies
- Pet allergies
- Pollen allergies
Each type of allergy has specific symptoms and treatments.
Symptoms of Allergies
The symptoms of allergies can range from mild to severe. The most common allergy symptoms include:
- Sneezing
- Itching of the nose, eyes or roof of the mouth
- Runny, stuffy nose
- Watery, red or swollen eyes (a condition known as conjunctivitis)
- A rash or hives
- Swelling
- Abdominal pain
- Diarrhea
- Difficulty breathing
- Anaphylaxis
In some severe cases, allergies can trigger a life-threatening reaction known as anaphylaxis.
Diagnosis of Allergies
If you have allergy symptoms, your doctor may recommend an allergy test. During an allergy test, your skin is pricked and exposed to small amounts of the proteins found in potential allergens. If you're allergic, you develop a raised bump or reaction.
Treatment of Allergies
The best way to treat allergies is to avoid the allergens. However, this is not always possible. Other treatments include medications, immunotherapy, and emergency epinephrine.
Prevention of Allergies
While you can't prevent allergies, you can take steps to control your symptoms. This includes avoiding known allergens, taking medications to control symptoms, and keeping your environment clean.