Cetrimin, also known as Cetirizine Hydrochloride, is a second-generation antihistamine H1 receptor antagonist with a fast onset of action and good efficacy after oral administration, and generally does not pass through the brain barrier, so it is weak in sedation and has few side effects. Cetirizine Hydrochloride is mainly used for the rapid relief of symptoms associated with allergic rhinitis, such as sneezing, itchy nose, nasal mucous membrane congestion caused by allergic rhinitis. It can be used to treat itchy, watery and congested eyes caused by allergic conjunctivitis, and for the relief of symptoms of chronic urticaria, such as itchy and windy skin. Also cetirizine hydrochloride is used to treat itchy skin caused by non-allergic diseases, such as psoriasis vulgaris, neurodermatitis, seborrheic dermatitis.