Any ophthalmic drop has the potential to impact visual acuity upon instillation due to the effect it has on the tear layer components. Studies have observed that taking artificial tears continuously over time tends to stabilize the tear layer thus minimizing the immediate drop in contrast sensitivity upon instillation. Measuring the visual effect of artificial tears, using contrast sensitivity as a measure, provides valuable information about the therapeutic effect of artificial tears that are meant to stabilize the tear film, thus improving visual acuity in dry eye patients.