What is an allergy?
Allergy is the result of the immune system overreacting to harmless stimuli in the environment.
Examples of stimuli or 'allergens' include pollen, dust, eggs and milk.
The body recognises these harmless allergens as foreign, which leads to white blood cells releasing antibodies.
Antibodies then trigger mast cells (another form of immune cell) to produce histamine and this promotes inflammation. You may have seen how inflammation manifests in your own body following injury or infection. Typically the inflamed part of the body becomes hot, red, swollen and very painful.
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