Hay fever, or allergic rhinitis, is caused by an allergic reaction to pollen; the body makes specific antibodies when pollen comes into contact with the mouth, eyes, nose or throat. The condition has become increasingly common and affects one in four of the population - that's around 13 million people.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/how-do-you-treat-hay-fever-in-children