| What is an Allergy? |
| Who Gets Allergies? |
| What Are the Signs and Symptoms of Allergies? |
| When do an Allergies Occur? |
| What are Some Common Allergens? |
| Is Allergy Inherited? |
There are three classic kinds of atopy:
atopic dermatitis (eczema), hay fever (seasonal allergic rhinitis) and allergic asthma.
Most allergy sufferers are atopic.
Atopy means that the individual has a genetic tendency to develop allergies.
In most developed countries up to 40% of the population will be atopic.
Even only one-half of them will develop allergic symptoms.
Atopic individuals are genetically prone to manufacture antibodies of the IgE class.
These IgE (immunoglobulin E) antibodies tend to react against allergens present in the environment (pollen, cat dander, moulds, house dust mite).
Atopy is therefore easily diagnosed in an individual who has a personal or immediate family history of allergies and on doing skin prick test they react to one or more
of the common environmental allergens. These individuals with the genetic predisposition must be exposed to the allergen either in their environment or in their diet.
So allergy is partly inherited and partly environmental.
If one of your parents has a respiratory allergy,
you have a 30 to 50 percent chance of developing one, though not necessarily the same allergy.
If both of your parents have respiratory allergies, the risk that you will develop an allergy goes up to 80%.