7H
Carboxymethylcellulose is a cellulose derivative that consists of the cellulose backbone made up of glucopyranose monomers and their hydroxyl groups bound to carboxymethyl groups. It is added in food products as a viscosity modifier or thickener and emulsifier. It is also one of the most common viscous polymers used in artificial tears, and has shown to be effective in the treatment of aqueous tear-deficient dry eye symptoms and ocular surface staining. The viscous and mucoadhesive properties as well as its anionic charge allow prolonged retention time in the ocular surface. Sodium carboxymethylcellulose is the most commonly used salt.