Loratadine is a second generation antihistamine used to manage symptoms of allergic rhinitis.

Due to their lack of sedative and CNS adverse effects, loratadine along with other second generation antihistamines have become preferable over their 1st generation counterparts in many clinical situations.

Loratadine is a piperidine histamine H1-receptor antagonist with anti-allergic properties and without sedative effects. Loratadine blocks the H1 histamine receptor and prevents the symptoms that are caused by histamine activity on capillaries, bronchial smooth muscle, and gastrointestinal smooth muscle, including vasodilatation, increased capillary permeability, bronchoconstriction, and spasmodic contraction of gastrointestinal smooth muscle. Loratadine does not cross the blood-brain barrier and does not cause central nervous system effects.