What are allergies?

Allergies are the body's instinctive response to external substances known as allergens, or allergy-causing agents. Almost everything external to the human body qualifies as an allergen.

Pollen makes some folks sneeze, while others might suffer an adverse reaction after consuming a specific food. Common allergens include: nuts, cosmetics, dairy products, dust, pollen, molds, poisonous plants, specific medicines, insect stings, seafood, tomatoes, chocolates, as well as certain fruits and grains.

What causes a person to become allergic?

Allergies occur when the body feels threatened by a foreign material ingested, inhaled, or simply touched by the skin.

When the external threat is perceived, the immune system responds by producing antibodies which cause various reactions to a allergen -- a sneeze, a gag, a rash. If an individual is sensitive to a specific allergen, he or she will react when exposed to it, while people not sensitive to that particular allergen remain unaffected. Genetics and environment both play a part in susceptibility to allergies.

What are the symptoms of allergies?

There are almost as many different symptoms as there are allergens and people! The degree of sensitivity to any particular allergen varies among individuals. Two people may both be allergic to cats, for example, but exhibit different reactions; one might sneeze, while other develops watery eyes or a rash. Among the most frequently observed symptoms of allergies are: