Levocetirizine is used to relieve runny nose; sneezing; and redness, itching, and tearing of the eyes caused by hay fever, seasonal allergies, and allergies to other substances such as dust mites, animal dander, and mold. It is also used to treat symptoms of hives, including itching and rash. Levocetirizine is in a class of medications called antihistamines. It works by blocking the action of histamine, a substance in the body that causes allergic symptoms. Levocetirizine comes as a tablet to take by mouth. It is usually taken once a day in the evening with or without food. Take levocetirizine at the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take levocetirizine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.