Excipient (pharmacologically inactive substance)
What is it?
Polyvinyl alcohol (C2H4O)x is a water-soluble synthetic polymer. It is used to increase viscosity in pharmaceuticals and as a lubricant and protectant in ophthalmic preparations. Polyvinyl alcohol is often found in over-the-counter eye redness and eye lubricant ("Tears") eye drops. Polyvinyl alcohol is the lubricant, and works by providing moisture to the eye, which helps relieve dryness and protects the eye from becoming more irritated.