* Hay fever -- Ragweed is a common cause of hay fever, or allergic rhinitis. The plant usually begins to pollinate in mid-August.
* Lingering warm weather -- While most people enjoy Indian summer, unseasonably warm temperatures can make rhinitis symptoms last longer. Mold spores can also be released when humidity is high, or the weather is dry and windy.
* Pesky leaves -- For allergy sufferers, raking presents its own problem. It can stir agitating pollen and mold into the air, causing allergy and asthma symptoms.
* School allergens -- It's not only seasonal pollen and mold that triggers allergies this time of year. Kids are often exposed to classroom irritants and allergy triggers, including chalk dust and classroom pets. Students with food allergies may also be exposed to allergens in the lunchroom. Those with exercise-induced bronchoconstriction (EIB) may experience attacks during recess or gym class.