WARNING ON ARTIFICIAL TEARS CONTAINING SODIUM HYALURONATE

Corneal calcification following intensified treatment with sodium hyaluronate artificial tears -- Bernauer et al. 90 (3): 285 -- British Journal of Ophthalmology This abstract discusses 5 cases of deep calcium deposition in the corea due to frequent use of hyaluronic acid artificial tears. All five required PKP! The abstract says:

"This is because of its high phosphate concentration and typically frequent instillation. Manufacturers and prescribers should be aware that topical preparations may contain considerable amounts of phosphate which may lead to sight threatening corneal complications."

The only drop I know with sodium hyaluronate is Aquify. The abstract does not define "frequent" but the full-text probably does.