Cetylpyridinium chloride monohydrate (Standard) is the standard substance of Cetylpyridinium chloride monohydrate, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. Cetylpyridinium chloride monohydrate (Hexadecylpyridinium chloride monohydrate) , a cationic quaternary ammonium compound, is used in certain classes of throat sprays, mouthwashes, lozenges, toothpaste, nasal sprays, and breath sprays. Cetylpyridinium chloride monohydrate has also been used as an ingredient in certain pesticides. It is an antiseptic with killing bacteria and other microorganisms. It can be potent in reducing gingivitis and preventing dental plaque. It may result in brown stains between the teeth and on the surface of teeth.