What is this for cetirizine?

Cetirizine is an antihistamine commonly used to relieve allergy symptoms such as sneezing, runny or itchy nose, and itchy or watery eyes. It is also effective in treating hives and itching associated with chronic skin conditions. Cetirizine works by blocking the action of histamine, a substance in the body that causes allergic symptoms. It is available over-the-counter and is often marketed under brand names like Zyrtec.