Tear Film Stability After Instillation of Over-the-Counter (OTC) Artificial Drops

Twenty (20) patients will be enrolled in this two-period crossover, randomized study design. During the course of the study, each patient will be treated with each test article in the clinic at separate visits. Following the informed consent procedure, a general ocular evaluation, including corneal and conjunctival staining and Schirmer testing, will be done and evaporometry assessments will be completed to determine baseline tear evaporation rate. This will occur before any test article is administered to the patient. Qualified patients will be randomized into two treatment groups. After 1 hour, in order to eliminate any residual sodium fluorescein, patients will be administered one drop of Systane® (40 µl) or Optive™ (40 µl) in each eye per randomization assignment. At 30 minutes following instillation of the drop, the evaporometry measurement will be repeated. These evaporometry tests (pre and post instillation of drops) will be performed in order to establish a comparison for later analysis. The estimated time in completing each study visit will be 180 minutes per visit. Patients will be asked to return to the clinic after 2 - 14 days for evaluation of the 2nd assigned crossover treatment (i.e. patients who initially received Optive will receive Systane and patients who initially received Systane will receive Optane). During the interim study periods, patients will be asked to continue their pre-study routine; using their pre-study ocular lubricant or other tear products at the same frequency. Any changes in the frequency of product use during the interim period or any changes in other concomitant medications will be carefully recorded. This is especially important since many prescription products (e.g., Claritan) have significant effects on lacrimal gland physiology. An effort will be made to schedule all study visits at approximately the same time of day in order to reduce diurnal variability. For the similar reasons, all patients will be asked not to use any lubricants or ocular medications for at least one hour prior to their office visits.