Hypromellose

Promotes corneal wetting by the stabilization and thickening the precorneal tear film and prolonging the tear film breakdown time, which is usually shortened in dry eye conditions. Hypromellose also acts to lubricate and protect the eye.

The surface active properties of the vehicles found in artificial tears solutions act to stabilize the tear film and increase tear viscosity to prevent delay tear evaporation and delay tear drainage.

In the intact eye, the corneal surface is moistened primarily by the mucin that is produced in the conjunctiva. Mucin is adsorbed on the corneal surface and forms a hydrophilic surface. This creates a moisture barrier. In the typical dry eye, and particularly in case of mucin deficiency, the application of artificial tear fluid is highly recommended. Both its surface activity and its adsorptive capacity make hypromellose optimal for this use. Hypromellose has a physical-chemical action and leads to, in an aqueous solution, a reduced surface tension as well as an increased level of viscosity. Hypromellose adheres well to the cornea and conjunctiva and provides ample moisture. Irritation symptoms caused by blinking, which occur in the case of tear fluid deficiency, are therefore decreased and symptoms of epithelial desiccation are also alleviated.