pollen allergy on white paper

background allergy pollen white paper allergic rhinitis hay fever seasonal sneezing itchy eyes nose throat watery congestion runny nasal symptoms triggers grass tree weed ragweed birch oak cedar elm maple asthma immunotherapy antihistamines decongestants corticosteroids avoidance exposure diagnosis treatment management prevention medication over- -counter prescription airborne particles immune response histamine inflammation sensitivity allergen reaction environment climate weather forecast count season spring summer fall winter outdoor activities indoor air quality filters hepa vacuum cleaning pets