Allergies are abnormal immune system reactions to things that are typically harmless to most people. When you're allergic to something, your immune system mistakenly believes that this substance is harmful to your body. (Substances that cause allergic reactions, such as certain foods, dust, plant pollen, or medicines, are known as allergens.) In an attempt to protect the body, the immune system produces IgE antibodies to that allergen. Those antibodies then cause certain cells in the body to release chemicals into the bloodstream, one of which is histamine (pronounced: his-tuh-meen).

Allergies of the skin is one of the most common problems seen by the allergist, and one of the most debilitating problems experienced by patients. From hives to swelling, to eczema and medication rashes, learn more about allergic skin rashes.Allergy is caused by an oversensitive immune system, which leads to a misdirected immune response. The immune system normally protects the body against harmful substances, such as bacteria and viruses.

When an allergen comes in contact with the body, it causes the immune system to develop an allergic reaction in persons who are allergic to it. When you inappropriately react to allergens that are normally harmless to other people, you are having an allergic reaction and can be referred to as allergic or atopic. Therefore, people who are prone to allergies are said to be allergic or "atopic."

Types of Allergies

Dust Mite Allergy: A dust mite allergy is an allergic reaction to a microscopic organism that lives in the dust that is found in most buildings and houses. Dust mites are a common cause of perennial allergic rhinitis. Dust mite allergy usually produces symptoms similar to pollen allergy and also can produce symptoms of asthma.

Mold Allergies: Mold allergies are most common during summer months. A mold allergy is simply an allergic reaction to common household molds. The Toxic Black Mold Information Center includes tips for finding, cleaning, and preventing indoor mold problems.

Food allergies occur when your immune system makes a mistake. Normally, your immune (say: ih-myoon) system protects you from germs and disease. It does this by making antibodies that help you fight off bacteria, viruses, and other tiny organisms that can make you sick. But if you have a food allergy, your immune system mistakenly treats something in a certain food as if it's really dangerous to you.

Latex Allergies from the rubber tree Hevea brasiliensis is an allergen in persons with significant cumulative latex exposure, such as those in the health care and rubber industries, as well as those undergoing repeated surgeries, especially if they undergo surgeries early in life. Symptoms of latex allergy may progress rapidly and unpredictably to anaphylaxis. The prevalence of latex allergy has increased as the use of rubber gloves in health care settings has increased. Airborne latex particles that adhere to the cornstarch used to powder gloves are a significant cause of respiratory symptoms and a source of sensitization. Once an individual has become sensitized, he or she may experience allergic symptoms when exposed to any product containing latex.

Herbal Medicine for Allergies

Several herbs hold hope for allergy sufferers. Although the precise prescription for an individual patient may require professional consultation, urtica (stinging nettles) can generally provide relief from acute attacks of hay fever. Eyebright can be useful for the symptoms of runny nose and watery eyes. Siberian ginseng, elder, and licorice (the root, not the candy) can also reduce symptoms associated with hay fever. Teas of Siberian ginseng can help reduce inflammation in the sinus area.