Tiny particles present in the air you breathe can produce allergies leading to Hay fever (Rhinitis) & Asthma. Symptoms include sneezing, stuffy nose, irritation of throat, nose, mouth & eyes. You can ultimately suffer from asthma. This type of allergy can happen all the year round or it can be seasonal when pollen count in the air is very high. Adults can get these allergies from dust mites that live in your carpets, bedding, curtains & furniture; pollen from trees, grass & weeds; pet fur or dead skin; spores of molds; cockroach saliva & waste.