The brand name for an allergy medication used to treat hay fever and other upper respiratory allergies is Allegra. Fexofenadine, a kind of antihistamine, is the active component of Allegra. Histamine, a chemical in the body that causes allergy symptoms, is blocked by this drug. Both a prescription and over-the-counter version of Allegra are available, and they can be taken with or without food. This medication frequently causes drowsiness, nausea, and headaches as adverse effects. Allegra and other allergy medications can be useful for treating and relieving allergy symptoms. Consult your doctor if you're thinking about taking this medication to determine whether it's good for you.
