Allergic rhinitis (AR), more commonly referred to as hay fever, is an inflammation of the nasal passages caused by allergic reaction to airborne substances. Symptoms include nasal congestion, a clear runny nose, sneezing, nose and eye itching, and tearing eyes. Post-nasal dripping of clear mucus frequently causes a cough. Loss of smell is common and loss of taste occurs occasionally. Nose bleeding may occur if the condition is severe.
There are two types of allergic rhinitis: seasonal and perennial. Seasonal AR occurs in the spring, summer, and early fall, when airborne plant pollens are at their highest levels. Perennial AR occurs all year and is usually caused by airborne pollutants.