Allegra relieves the itchy, runny nose, sneezing, and itchy, red, watery eyes that come with hay fever. It is also used to relieve the itching and welts of hives. Allegra is a type of antihistamine that rarely causes drowsiness.
In addition to the antihistamine in Allegra, Allegra-D also contains the nasal decongestant pseudoephedrine.