Cetirizine is a second-generation antihistamine used to relieve allergy symptoms, including sneezing, runny nose, watery eyes, and skin rashes. It is effective for hay fever, allergic rhinitis, and chronic hives. Unlike older antihistamines, it causes minimal drowsiness.

It works by blocking histamine, a chemical that triggers allergic reactions. Cetirizine is available in tablets, syrups, and chewable forms. Side effects are usually mild but may include dry mouth, drowsiness, or headache. It is safe for long-term use and is often recommended for seasonal or year-round allergies.