What exactly are allergies? Oh, we all know how allergies affect us. The itching, sneezing, watery eyes, runny nose and other symptoms of allergies often send us running for the Sudafed. But what is it that causes allergies?

Allergies are a result of the body's immune system. What happens is the immune system targets a non-harmful substance, like pollen and attacks it like it is a malicious virus. An extremely sensitive immune system can actually harm the organ in the body that it is thinking it is protecting when it goes overboard.

Most doctors believe that allergies are triggered by a protein in the allergen. The protein that the person is allergic to causes the white blood cells in the body to act as if the allergen is invading the body and they go into attack mode. They produce a large quantity of antibodies that attach themselves to mast cells in the body. These mast cells have histamines and when histamines enter the body in too high of quantities, they cause problems.

Here is what happens. Let's look at ragweed, for example, since that is one of the most common allergens. Ragweed pollen is inhaled, thus entering the body. The antibodies that are bound to the mast cells recognize the proteins in the ragweed pollen. Their reaction is to bond to those proteins, while staying with their mast cell. By binding to both places, the antibody alerts the complement complex proteins. They come and destroy the bonded particle. When the mast cell is destroyed, it releases histamine to the body. Histamines cause blood pressure to drop and blood vessels to dilate. These symptoms cause the spaces to fill with fluids, causing all of the traditional symptoms of allergies.

What is interesting is that even in our highly developed society, we do not totally understand the process of allergies. Once someone has begun showing signs of an allergy to a particular substance, they will often exhibit allergies to similar substances. Another interesting thing about allergies is that they can build up. Sometimes a person can have a mild reaction to a substance and later they will exhibit even stronger symptoms. A severe reaction to an allergen is called anaphylactic shock, a condition where the body starts to shut down, after breaking out into hives and swelling. If you are exhibiting an allergic reaction accompanied by swelling or hives, go to the hospital right away. Anaphylactic shock can lead to death, by harming the brain, kidneys, or causing the brain to swell shut. To treat anaphylactic shock, you will need an injection of epinephrine, but it must be given quickly, before the body has a chance to have serious damage.

If you think your child might be prone to allergies, you can take your child for tests. The most common way to test for allergies is through a scratch test. A scratch test is where a doctor applies a small bit of an allergen to a scratch on the arm or back and then watches for swelling. This is not used often in small children, however, as it can actually trigger a reaction. For small children, parents just need to watch for signs of allergies and talk to the doctor if they have concerns.