Fexofenadine is a second generation selective non-sedating histamine (H1) antagonist indicated for the relief of symptoms associated with seasonal allergic rhinitis. It is the predominant active metabolite of terfenadine. Fexofenadine is a selective antihistamine used to relieve allergic rhinitis (seasonal allergy) symptoms including sneezing, runny nose, itching, and watery eyes. Fexofenadine is available alone and in a combination product.
Fexofenadine is an antihistamine. Antihistamines work against the naturally occurring chemical histamine in your body. Fexofenadine is used to prevent sneezing, runny nose, itching and watering of the eyes, and other allergic symptoms. It is similar to the other second generation antihistamines loratadine (Claritin), cetirizine (Zyrtec) and azelastine (Astelin). Histamine is a chemical that is responsible for many of the signs and symptoms of allergic reactions, for example, swelling of the lining of the nose, sneezing, and itchy eyes. Histamine is released from histamine-storing cells (mast cells) and then attaches to other cells that have receptors for histamine. The attachment of the histamine to the receptors causes the cell to be "activated," releasing other chemicals that produce the effects that we associate with allergy, e.g., sneezing. Fexofenadine blocks one type of receptor for histamine (the H1 receptor) and thus prevents activation of H1 receptor-containing cells by histamine. Unlike the first generation antihistamines, fexofenadine and other second-generation antihistamines do not readily enter the brain from the blood, and, therefore, they cause less drowsiness.
Fexofenadine is used to relieve hay fever and allergy symptoms, including runny nose; sneezing; and red, itchy, tearing eyes. Fexofenadine is in a class of medications called antihistamines. It works by blocking histamine, a substance in the body that causes allergic symptoms. Fexofenadine may cause less drowsiness than other antihistamines. Fexofenadine hydrochloride is a pharmacologically active metabolite of terfenadine and is a non-sedating, selective histamine H1-receptor antagonist.
Chemical name: α,α-dimethyl-4-[1-hydroxy-4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]butyl]benzeneacetic acid
CAS No.: 38452-21-8
Molecular formula: C32H39NO4
Molecular weight: 501.67