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Gregg:  Greetings!

I use an Allergan eyedrop product called "Refresh Celluvisc" which is
packaged into very small individual doses.  A box of 30 of these
single-use containers is a couple of bucks.

The only thing in them is salt water and a soluble cellulose, which
increases the viscosity to help lubricate the eye.  (Some therapeutic
drops also include a viscosity-increasing component to cause the
active ingredients to remain in the eye longer.)

These drops are specifically designed to to allow a user to "...avoid
the use of potentially irritating preservatives found in some bottled
eye drops." (From the package label.)

I suspect that there are other manufacturers of similar products.

Good luck!

earle
(I am an engineer and not a health-care professional.)
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