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Allergy triggers

There are a number of different allergy-causing substances. The most common include pollen, house dust mites, mould, pets, insect stings, latex, and certain foods and medication. If you have an allergy your symptoms can range from mild eye irritation and congestion to a more severe reaction causing generalised swelling and difficulty breathing.

Plus, if you have asthma, a reaction to any offending allergy-causing substance can worsen your asthma symptoms. Still there are steps you can take to prevent and treat allergy attacks when they occur.


Exposure to pollen can trigger hayfever or seasonal allergies. Symptoms include sneezing, runny nose, nasal congestion, and itchy, watery eyes. Treatments include over-the-counter and prescription antihistamines, decongestants, steroid nasal sprays, and medicines that combine antihistamines and decongestants. Allergy injections, called immunotherapy, are also an option for some people.

Prevent hayfever symptoms by staying indoors on windy days or when pollen counts are high, closing windows, using air conditioning, (if you have it) and refraining from hanging clothes out to dry during the pollen season.

House dust mites

House dust mites are microscopic organisms that live in house dust. Symptoms of house dust mite allergy are similar to pollen allergy but often occur year round rather than just seasonally. Treatment may include medications such as antihistamines, decongestants, or nasal sprays.

Help prevent house dust mite allergy symptoms by considering putting dust mite covers over mattresses, pillows, and box springs, using hypoallergenic pillows, washing sheets weekly in hot water, and keeping all areas of the house, especially the bedroom, free of dust collecting-items including cuddly toys, curtains, and carpet. The humidity should be kept between 30% and 45%.


Moulds are parasitic, microscopic fungi with spores that float in the air like pollen. It is a common trigger for allergies and can be found in damp areas such as basements or bathrooms, as well as in grass, leaf piles, hay, mulch, or under mushrooms.

Symptoms of mould allergies can occur seasonally, especially in the summer and autumn or through out the year if mould is in your home. The symptoms are similar to those of pollen and house dust mite allergies and include sneezing, congestion, itchy, and watery eyes, runny nose, and coughing. Treatments are the same as those for house dust mites or pollen.

Help prevent mould allergies by avoiding activities that trigger symptoms, such as raking leaves. Make sure moist places in the home, such as the basement and bathrooms, are well ventilated. Look for areas of water damage and repair those spots. Keep indoor plants to a minimum since their soil harbours and promotes mould growth.

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