Getting to know

Most frequent airborne allergens present in the air indoors are house dust mites, animal allergens, indoor moulds and cockroaches (the last one being an increasing problem in North America and in Asia). Unlike outdoor allergens, indoor ones are present in the air during the whole year. Consequently if you are allergic to them your symptoms will probably present all year round. However, symptoms can be worse during certain periods of the year (specific for each kind of allergen) when favourable conditions promote an increase in allergen concentration.