To compare the effectiveness of 1.0% carboxymethylcellulose (CMC) (Refresh Liquigel, Allergan, Inc., Irvine, CA) and propylene glycol/polyethylene glycol 400 (PG-HPG) (Systane, Alcon, Fort Worth, TX) in providing relief of dry eye symptoms and signs.
To evaluate patient comfort and drop preference, patients were given CMC in one eye and PG-HPG in the other. Five minutes after the initial drop application, patients were questioned on overall preference and comfort, as measured by stickiness, blurring, and soothing. Patients were then randomized to receive CMC or PG-HPG in both eyes for 1 week. Fluorescein staining was evaluated at baseline and week 1.
Of patients with a preference, more patients preferred CMC than PG-HPG. Thirty-six percent preferred CMC, and 24% preferred PG-HPG. More (35%) patients found CMC to be more soothing than PG-HPG (22%). After 1 week of treatment, eyes treated with CMC consistently showed less ocular surface staining than did eyes treated with PG-HPG. Mean corneal staining score in the inferior region was significantly lower in the CMC group than in the PG-HPG group (P = 0.008) at week 1. CMC provided a statistically significant decrease in mean corneal inferior staining (P < 0.001), whereas the PG-HPG group (P = 0.185) had no significant change. In the temporal conjunctival region, CMC provided a significantly lower mean staining score than PG-HPG after 1 week of treatment (P = 0.005).
Patients found CMC to be more comfortable than PG-HPG. After 1 week of use, CMC provided greater relief of dry eye signs and symptoms than PG-HPG.