Ocular surface lubricant

Ocular surface lubricants, commonly known as artificial tears or tear substitutes, are therapeutic agents designed to supplement or replace the natural tear film in patients with ocular surface diseases (PubMed, 2008). They function by providing hydration, reducing friction between the eyelid and the cornea, and stabilizing the tear film's lipid, aqueous, and mucin layers (Oxford Academic, 2024). These agents typically consist of viscosity-enhancing polymers such as carboxymethylcellulose or sodium hyaluronate, which mimic the viscoelastic properties of natural tears and increase the retention time on the eye (eOphtha, 2022). In addition to physical lubrication, some modern formulations act as osmoprotectants, shielding the corneal epithelium from the hyperosmotic stress that characterizes dry eye syndrome (Midlands Medicines, 2013). While primarily used for symptomatic relief, specialized lubricants like recombinant human lubricin are also utilized to promote the healing of the ocular surface and restore the integrity of the glycocalyx-mucin interface (Current Ophthalmology Reports, 2025). They remain the cornerstone of first-line therapy for maintaining ocular comfort and visual clarity in conditions like keratoconjunctivitis sicca (SciELO, 2016).

Other names

Artificial tearsTear substitutesOcular lubricantsLacrimomimeticsDemulcents

Physical supplementation of the tear film layers to provide hydration, increase viscosity, and reduce mechanical friction on the ocular surface (PubMed, 2008; Oxford Academic, 2024).