The term allergic rhinitis is the proper medical term for "hay fever."

Rhinitis is inflammation of the nasal passages which can cause symptoms such as sneezing, itching, nasal congestion, runny nose, and postnasal drip (when mucus drains from the sinuses down the back of the throat). Most people develop symptoms of allergic rhinitis in childhood or young adulthood, though it can start at any age. At times, patients will have no symptoms, and others will have them only at certain times of the year. Symptoms are worst in children and adults in their 30s and 40s, though the severity of the symptoms varies throughout a person's life.