Hayfever, also known as seasonal allergic rhinitis, is an allergy to pollen, which is produced by trees, plants, and flowers. According to Allergy UK, hayfever affects 10-30% of all adults and up to 40% of children, making it a prevalent ailment. The symptoms are normally at its worst during the spring and summer, when pollen counts are at their peak, but it affects some people all year. When you’re exposed to pollen, your immune system incorrectly interprets it as a threat. Antibodies are produced by the immune system in response to this perceived threat. These tell your eyes, nose, mouth, and throat to make inflammatory chemicals, which is what produces the symptoms.