The preservatives in artificial tears are making my eyes tire more quickly from computer use. hope this can be undone by switching, ie, not permanent?

Artificial tears: There are over the counter preservative free alternatoves. They come in individual vials and each last 24hours after opening. Give those a try.

Artificial Tears: Stop using the drops. Doubtful it is permeant. Consider having your eyes examined by Ophthalmology to see if there is a better treatment for dry eyes and eye fatigue. Perhaps you need glasses or anti reflective screen.