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Updated: Aug 2, 2026
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Effect of Artificial Tear Formulations on the Metabolic Activity of Human Corneal Epithelial Cells after Exposure to Desiccation
Published on: May 2, 2020
Colloid osmotic pressure of artificial tears
1Department of Ophthalmology and Visual Sciences, Texas Tech University Health Sciences Center, Lubbock.
Journal of Ocular Pharmacology
|January 1, 1985
Summary
Colloidal osmolality, or oncotic pressure, plays a key role in tear fluid balance. HypoTears artificial tears have significantly higher oncotic pressure, improving corneal health.
Area of Science:
- Ophthalmology
- Physiological Optics
- Biomedical Engineering
Background:
- Colloidal osmolality (oncotic pressure) of tears is largely unstudied compared to total osmolality.
- Despite its small magnitude, oncotic pressure is crucial for tissue water balance.
- Previous research utilized oncotic pressure in formulations like Dehydrex for corneal health.
Purpose of the Study:
- To determine and compare the oncotic pressure of marketed artificial tear preparations with natural tears and corneal stroma.
- To investigate the role of oncotic pressure in the efficacy of artificial tear formulations.
Main Methods:
- Measurement of total osmolality and oncotic pressure for artificial tear solutions.
- Comparison of measured values with those of natural tears and corneal stroma.
Main Results:
- HypoTears demonstrated an oncotic pressure approximately sixty times higher than a leading artificial tear.
- The oncotic pressure of HypoTears is comparable to that of Dehydrex.
- This high oncotic pressure, rather than hypoosmolality, is likely responsible for HypoTears' favorable patient acceptance.
Conclusions:
- Artificial tear formulations with high oncotic pressure, like HypoTears, can be effective.
- Such formulations may help ameliorate microcystic epithelial edema and improve corneal epithelial adhesion.
- Further research into oncotic pressure's role in artificial tears is warranted.
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