In much of the U.S., spring allergies may begin as early as February and last until summer. Tree pollen is a common springtime allergen, although often people have allergies to three or four species of trees and plants. Airborne mold spores represent another common culprit.
Monitoring outdoor pollen counts can be helpful, but you’ll only benefit from staying indoors on high-count days if the elevated levels include pollens to which you’re allergic (allergy testing can help you determine your individual allergies).
A better bet is to be prepared to tackle your springtime allergies regardless of what the day’s pollen count may be.
How Do Seasonal Allergies Develop?
Seasonal allergies, sometimes called hay fever, affect up to 8 percent of the U.S. population.1 They cause a number of bothersome symptoms including sneezing, stuffy or runny nose, watery and itchy eyes, and itching in your nose, mouth or throat.
Allergies are your body’s reaction to particles that it considers foreign (allergens). The first time your body encounters an allergen, your plasma cells release immunoglobulin E (IgE), an antibody specific to that allergen.
IgE attaches to the surface of your mast cells, which are found in great numbers in your surface tissues, such as your skin and nasal mucous membranes, where they help mediate inflammatory responses. Mast cells release a number of important chemical mediators, one of which is histamine.
The second time your body encounters a particular allergen, within a few minutes your mast cells become activated and release a powerful cocktail of histamine, leukotrienes, and prostaglandins, which trigger the entire cascade of symptoms you associate with allergies.