These can be
outdoor allergens like ragweed, grasses and pollens, as well as indoor irritants like mold, dust mites, cleaning chemicals and even fabrics like wool or cotton.
Outdoor allergens like trees, mold spores, grass and pollen cost hay fever sufferers some 4 million workdays each year.1
Not exact matches
As you might guess,
outdoor allergens can be more of a problem during certain seasons
like spring and fall while indoor
allergens like dust and molds tend to be a problem year round.