ALERTRIZ 5MG TABLET contains levocetirizine, a non-drowsy antihistamine. It's less likely to make you feel sleepy than some other antihistamines. However, some people still find it makes them feel quite sleepy, which is used to treat allergies as it blocks the effects of a chemical messenger known as histamine, which is naturally involved in allergic reactions. ALERTRIZ 5MG TABLET is widely used to treat hay fever (an allergy caused by pollen or dust), conjunctivitis (red, itchy eye), eczema (dermatitis), hives (red, raised patches or dots), reactions to insect bites and stings and some food allergies.