Allergy occurs when a person's immune system reacts to substances in the ENVIRONMENT that are harmless for most people. It has become most common in UAE. These substances are known as allergens and are found in HOUSE dust mites, pets, pollen, insects, molds, foods and some medicines.

Atop is the genetic (inherited) tendency to develop allergic diseases. People with atop are said to be a topic.

When atopic people are exposed to allergens they can develop an immune reaction that leads to allergic inflammation (redness and swelling).

This can then cause symptoms in the:

Nose and/or eyes - hay fever (allergic rhinitis/conjunctivitis)

Skin - eczema, hives (urticarial)

Lungs - asthma

A substance that is an allergen for one person may not be for another - everyone reacts differently. The likelihood (or RISK) of developing allergies is increased if other family members suffer from allergy or asthma.

See more at: http://www.allergy.org.au/patients/about-allergy/what-is-allergy#sthash.oY8dMgkU.dpuf

What happens when you have an allergic reaction?

When a person who is allergic to a particular allergen comes into contact with it, an allergic reaction occurs. This begins when the allergen (for example, pollen) enters the BODY, triggering an antibody response. The antibodies attach themselves to special cells, called mast cells. When the pollen comes into contact with the antibodies, the mast cells respond by releasing certain substances, one of which is called histamine. When the release of histamine is due to an allergen, the resulting swelling and inflammation is extremely irritating and uncomfortable.

The most common causes of allergic reactions in UAE are:

Dust mites

Pollen

Cats and other furry or hairy animals such as dogs, horses, rabbits and guinea pigs

Insect stings (bed bugs, cockroaches etc.)

Molds

Which areas of the body may be affected?

Depending on the allergen and where it enters your body, you may experience different symptoms. For example, pollen, when breathed in through the nose, usually causes symptoms in the nose, eyes, sinuses and throat (allergic rhinitis).

The nose, eyes, sinuses and throat

When allergens are breathed in, the release of histamine causes the lining of your nose to produce lots of mucus and to become swollen and inflamed. It causes your nose to run and itch and violent sneezing may occur. Your eyes may also start to water and you may get a sore throat.

The lungs and chest

Asthma can sometimes be triggered during an allergic reaction. When an allergen is breathed in, the lining of the passages in the lungs swells and makes breathing difficult. Not all asthma is caused by allergy, but in many cases allergy plays a part.

The skin

Skin problems such as eczema (dry, red, ITCHY SKIN) and urticarial (also known as hives) often occur. Hives are white itchy swellings which look and feel like insect bites. Food may be a factor in some cases of hives and eczema. More information is available on the ASCIA website