NCIt definition : A third generation, non-sedating, selective histamine H1 receptor antagonist, with
antihistamine, anti-inflammatory and potential anti-angiogenic activities. Levocetirizine
competes with endogenous histamine for binding at peripheral H1-receptor sites on
the effector cell surface. This prevents the negative symptoms associated with histamine
release and an allergic reaction. In addition, as histamine plays an important role
in angiogenesis during an allergic inflammatory reaction, blocking the action of histamine
may modulate the expression of proangiogenic factors and thus may prevent angiogenesis.
As a third-generation histamine H1 receptor antagonist, levocetirizine has fewer side
effects than most second-generation antihistamines.;