Diquafosol

Diquafosol, or diquafosol tetrasodium, is a prescription ophthalmic solution used for the treatment of dry eye disease. It is a P2Y2 receptor agonist that stimulates secretion of aqueous fluid and mucins from conjunctival epithelial cells and goblet cells, helping to restore tear film thickness and stability.

Indications and use: It is indicated for symptomatic dry eye in adults and has been studied in both aqueous-deficient and mucin-deficient subtypes. Dosing typically consists of one drop in the affected eye six times daily. Administration usually requires removal of contact lenses before dosing and waiting several minutes before reinsertion.

Mechanism of action: By activating P2Y2 receptors on the ocular surface, diquafosol increases chloride ion transport and water movement, and promotes mucin secretion from goblet cells, contributing to a more stable tear film.

Clinical efficacy: Randomized trials have reported improvements in tear break-up time, corneal and conjunctival staining, and patient-reported symptoms compared with baseline or artificial tears, though results vary and some studies show modest benefits.

Adverse effects and safety: The most common adverse events are transient ocular irritation at drop administration, foreign body sensation, conjunctival hyperemia, and blurred vision. Serious ocular adverse events are rare. Caution is advised in patients with active ocular infection or hypersensitivity to the drug.

Regulatory status: Diquafosol is approved in several Asian countries for dry eye but is not approved by the U.S. FDA. Availability and labeling vary by country.