Freeze-dried extracts of pollen. Pollen serves as one of the most common triggers for seasonal allergies on a global scale. Depending on the time of year, weeds, grasses, and trees release pollen as part of their reproductive process. Although the wind carries these tiny and lightweight pollen grains, unfortunately, they often find their way into our noses, eyes, and lungs. Despite their delicate and innocent appearance, they can elicit allergic reactions in certain individuals, commonly known as hay fever. Symptoms typically include a runny nose, sneezing, and itchy eyes, with some people also experiencing lower respiratory symptoms such as asthma.

In individuals prone to allergies, their immune system responds to allergenic proteins by producing IgE antibodies, a process referred to as sensitization. These antibodies then attach to receptors on mast cells and basophils, which are the cells responsible for allergic diseases. When a sensitized person encounters pollen during the appropriate season, these effector cells release various mediators, including histamine. The collective action of these mediators is what triggers the onset of allergic symptoms.