John has an allergy to certain kinds of plant spores that cause him to sneeze, cough, and his eyes to swell. It is sometimes difficult to identify which plants are causing his irritation. The doctor may introduce many types of plants that are available during the time of year he becomes affected. He follows an allergy pathway of trial and error until he finds the one that causes the symptoms. The doctor said that although the plant spore may not be prevented from being in the environment, after being identified, a medication can be used to help calm the symptoms and help John live more comfortably during that particular season.