When there are unusual responses from your body to common harmless things, you are said to be suffering from allergy. These things are known as allergens, which you may inhale, swallow or these may contact your skin, causing allergy.
Allergens appear through pollen, house mites, food, insect bites, latex, bacteria, medicine, or some atmospheric conditions. These reactions can be localized in a particular area or it can extend to large parts of the body.
The human body has defensive arrangements, by which through experience it remembers the invading bacteria. It is this ability of the body which is put into practice in creating vaccines so that immunity is formed in the body, where immunological memory of the disease is created. Allergy results when the immune activity in the body mistakes innocent allergens into harmful ones.
The development of allergic reaction is illustrated below:
Suppose there is a field over which pollen grains have formed a cloud, though invisible, which is carried by wind to a different city. There, a child who has never been exposed to such substances breathes the pollen.
The child’s immune activity overacts and produces a huge quantity ofÂ antibodies, most of them attaching to the nasal passages and respiratory tract, result in allergy to the child, because the cells consist of strong chemicals, the most common being histamine.
When the child later breathes similar pollen again, pollen-protein bind themselves into the antibodies on the surface of the cells, resulting in a sort of blow-up, destroying pollen apart from damaging the tissues which are surrounding it.
This results in sneezing, headaches, stuffy head, watering eyes, etc, which are allergic reaction to the pollen.
You will thus realize that allergy is caused by a variety of responses which your body produces in response to a number of usually harmless commonplace things.
Your system may develop allergy to very common things like dust mites, extreme weather conditions like very cold weather and result in skin rashes, sneezing etc. You will have to recognize what is causing allergy, as these particles can have different effects on different people and try to avoid them, which will automatically avoid allergic reactions.