Allergies

Hypersensitivity of Immune System in Human Body causes Allergic Reaction, the contact of any foreign substance cans result into inappropriate Response by Immune System. These Substances are harmless in nature but to an Allergic these Allergens can prove to be harmful.
Everyone has different Allergens (foreign substance) which there System react to, it is very common Disease in many Countries.
The Severity of Allergies varies from small time redness irritation to potentially life threatening situations.

Signs & Symptoms

There are many different types of Allergies and each of them have different symptoms , according to the patient there can be either small symptoms which can be dealt with like sneezing, watery eyes, tingling, fatigue, swelling, itching etc, but in some rather serious cases a serious condition can occur called as Anaphylaxis.
Anaphylaxis is potentially life threatening if not dealt with immediately, the patient loses consciousness, drop in blood pressure is seen, confusion, light-headedness, shortness of breath, cramps, swelling, hives are likely to occur, Strict Medical Attention is required for the patient.

Causes

Major Cause of Allergy is the Oversensitivity on Immune System in human body, the immune system identifies harmless foreign substance as harmful pathogens and try to protect ourselves from it. To Protect us from that the Immune System produces antibodies which react to allergen, it releases immounoglobulin E (IgE), which fights the allergens. Another chemical is Histamine which causes tightening of muscles, blocking of vessels, etc.

Treatment

Treatment of Allergies can be done in several ways, but the first of them is to Recognize the Allergen which triggers the Allergic Reaction in you, this can help you avoid any contact with the Allergen respective to you.
Secondly, we can use proper medications which react to the allergic reactions and cancel out the reaction, many severe cases of allergic reactions required medications. Prominent Idea is to Avoid the Allergen.
Thirdly, Immunotherapy is practiced in severe cases of Allergies where we try to immune the body from reacting to Allergen, this is a long term Treatment, where administration of regular Allergen is done to reduce tendency of Immune System to produce IgE.