Carboxymethylcellulose Sodium (CMC)
CMC is a water-soluble polymer that retains water effectively. When used in eye drops, it helps to increase the moisture content of the tear film, providing hydration to the eyes and alleviating dryness.
Key Functions & Health Benefits
Increase tear viscosity – Thickens the tear film, helping it to stay on the eye longer and provide sustained moisture. Forms a protective layer – Create a protective barrier over the eye surface, shielding it from irritants.
How It Works
The mechanism of Carboxymethylcellulose Sodium in eye drops involves its high water-binding capacity, which allows it to form a viscoelastic protective film on the ocular surface, mimicking natural tears, reducing tear evaporation, and enhancing tear film stability for prolonged hydration and relief from dryness.
Clinical Evidences
This study evaluates the efficacy of Carboxymethylcellulose (CMC) 0.5% combined with Glycerin 0.9% and Balanced Electrolytes versus plain CMC 0.5% for keeping the ocular surface moist in individuals with dry eye symptoms. Conducted as a two-arm, open-label, parallel design study on 52 participants, Schirmer’s tests showed statistically significant improvements in tear production at 1 and 3 hours post-application for the CMC-Glycerin combination compared to plain CMC, with moisture levels increased by 23% and 26%, respectively. The study concludes that the combination provides better and prolonged hydration, highlighting the role of glycerin and electrolytes in enhancing artificial tear efficacy.
