What is an allergy?
You have an allergy when your body overreacts to things that don't cause problems for most people. These things are called allergens. Your body's overreaction to the allergens is what causes symptoms.
What is hay fever?
Hay fever, also known as allergic rhinitis (say: “rine-EYE-tis”), is an allergic reaction to pollen. Symptoms of hay fever are seasonal, meaning you will feel worse when the pollens that affect you are at their highest levels. Hay fever is the most common form of allergy. It affects 1 in 5 people.
Written by familydoctor.org editorial staff