Carboxymethyl cellulose (CMC) or cellulose gum is a cellulose derivativewith carboxymethyl groups (-CH2-COOH) bound to some of the hydroxyl groups of the glucopyranose monomers that make up the cellulose backbone.
It is often used as its sodium salt, sodium carboxymethyl cellulose.
CMC is used in food under the E number E466 as a viscosity modifier or thickener, and to stabilize emulsions in various products including ice cream. It is also a constituent of many non-food products, such as toothpaste, laxatives, diet pills, water-based paints, detergents, textile sizing, and various paper products. It is used primarily because it has high viscosity, is nontoxic, and is generally considered to be hypoallergenic as the major source fiber is either softwood pulp or cotton linter. CMC is used extensively in gluten free and reduced fat food product
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash,itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
None are recorded.
Source: Wikipedia, https://en.wikipedia.org/wiki/Carboxymethyl_cellulose