Gel drops have a preservative in them that you really should not use more than six times a day.

The artificial tears (non-gel) usually do not have any preservative in them and can be used as much as you want. (always check to make sure there's no preservative)

I had extremely dry eyes last month (allergies) and was using the gel drops until my eye doctor told me to just use artificial tears. (I use Refresh Tears) He also gave me a Rx drop that's for allergies. That's one drop a day and no more.

The gel drops were making my eyelashes and eyelids all crusty and icky. Now I save the gel drops for just before bed. The gel stays in the eyes longer than the artificial tears.

I get thirsty at night really bad, and try to keep a bottle of water nearby.