Allegra

Fexofenadine, sold under the brand name Allegra among others, is an antihistamine "pharmaceutical drug" used in the treatment of allergy symptoms, such as hay fever and urticaria.

Therapeutically, fexofenadine is a selective peripheral H₁ blocker. It is classified as a second-generation antihistamine because it is less able to pass the blood–brain barrier and cause sedation, compared to first-generation antihistamines.

It was patented in 1979 and came into medical use in 1996. It is on the World Health Organization's List of Essential Medicines. Fexofenadine has been manufactured in generic form since 2011. In 2021, it was the 262nd most commonly prescribed medication in the United States, with more than 1 million prescriptions.

Allegra help sponsor the Sprout premiere of Day of the Diesels on August 24th 2011.