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What is an Allergy?
An Allergy is an over-reaction of the immune system to invasion, causing inflammation when it is not needed.
What are the main causes of Allergy?
Nasal allergy (Allergic Rhinitis) is triggered by exposure to common natural and man-made materials including pollens, house dust mite faeces and fungus spores. These materials are called Allergens when they act to induce the signs and symptoms of allergic rhinitis.
Hayfever (Seasonal allergic rhinitis) is usually caused by by pollens (primarily grasses and trees) in spring and fungal spores in autumn, hence its seasonality.
What are the main symptoms?
The signs (what you can see, eg. a runny nose) and symptoms (what you can only feel, eg. an itch) of allergic rhinitis are generally restricted to the nose and eyes. The symptoms start very rapidly after allergen challenge. Sneezing begins within 2 minutes, a runny nose within 10 minutes and a blocked nose at about 15-20 minutes. The cardinal symptoms are:
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