Carboxymethyl Cellulose Sodium (CMC Sodium)

• Type: Lubricant & thickening agent

• Main Use: Commonly used as an artificial tear for dry eyes and as a thickener in medicines and foods.

How It Works (for the eyes)

• It coats the surface of the eye and holds moisture, helping to relieve dryness, irritation, and discomfort.

• Works like natural tears — forming a protective film over the cornea to keep it hydrated.

Forms Available

• Eye drops (single-dose vials or multi-dose bottles)

• Sometimes used in oral medicines and food as a stabilizer or thickener

Common Uses

• Ophthalmic use:

  • Dry eye syndrome

  • Eye irritation from wind, sun, or screen use

  • After eye surgery to keep the eye surface moist

• Non-ophthalmic use:

  • Thickener in syrups, tablets, and some foods

Advantages

• Generally very safe and gentle

• Non-medicated — just a lubricant, so it can be used frequently

• Available in different viscosities (thickness levels) — thicker ones last longer but may blur vision slightly right after use

Possible Side Effects

• Temporary blurred vision right after putting in drops

• Mild stinging or burning (rare)

• Allergic reaction is very uncommon

Precautions

• If using with other medicated eye drops, wait at least 5 minutes between them.

• Choose preservative-free versions if you have sensitive eyes or need frequent use.