<unk> , 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,<unk>  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.<unk>  has been manufactured in generic form since 2011. In 2019, it was the 283rd most commonly prescribed medication in the United States, with more than 1million prescriptions.
Fexofenadine
Ecallantide
Cetirizine
Terfenadine
Anakinra
Budesonide
Mibolerone
Ciclopirox