This article explains the basics of an allergic reaction. Learn what happens when your immune system goes on high alert.

Anyone can get them, at any age. You could develop them as a child, or you might not have any symptoms until you’re an adult.

While your problem may seem to start in the nose or the eyes, allergies actually come from an immune system run wild.

Worsening of asthma symptoms can be triggered by allergies, which can temporarily increase the inflammation of the airways.

There's no cure but you can take steps to curb springtime allergies, from medication to household habits.

Summer allergies are usually triggered by pollen from grasses and weeds.

Ragweed, mold, and dust mites are the biggest allergy triggers in the fall.

With indoor allergies such as mold and dust mites, you may notice symptoms more during winter, when you spend more time inside.

An allergist may be able to help identify your allergy triggers. Several different types of allergy tests are used to do this.

If you think you have allergies, think about seeing a doctor who can tell you whether you do or not.

Skin testing is one way your doctor can check on what causes your allergy symptoms.

Allergy blood tests detect and measure the amount of allergen-specific antibodies in your blood.

Learn all about the different over-the-counter and prescription medicines that can help ease annoying symptoms.

When medicine is needed to stem allergy symptoms, antihistamines are often first in line.

When allergies make your nose stuffed up, an antihistamine generally won't help. But a decongestant might.

When allergies strike, nasal sprays can help. There are many different types, and most work faster than pills.