Carbomer and sodium hyaluronate eyedrops for moderate dry eye treatment

Purpose. This randomized, double-masked study compared the effectiveness of two commercially available ocular lubricants containing either 0.31% Carbomer 934 or 0.18% sodium hyaluronate (SH) in treating moderate dry eye. Methods. Sixty-five subjects with dry eye were recruited and supplied with eyedrops containing either Carbomer or SH to use for a month. Principle outcome measures were the severity of symptoms of ocular irritation, tear break-up time without (NIBUT) and with (TBUT) fluorescein, and corneal and conjunctival staining with fluorescein and lissamine green, respectively. At the end of the experiment, subjects were also asked, on average, how many times a day they used the treatment and the duration of any postinstillation blur. Results. Both Carbomer and SH reduced the symptom severity and ocular surface staining, but neither had a lasting effect on NIBUT or TBUT. The treatment effects of Carbomer and SH were equivalent for symptoms, NIBUT and TBUT. However, for both corneal and conjunctival staining, SH outperformed Carbomer in improving the integrity of the ocular surface. There was no difference in the average instillation frequency of the two products. Visual disturbance after instillation of either formulation was generally short, but lengthy periods of blur were significantly more common after the use of Carbomer. Conclusions. Both of the eyedrops trialled are suitable for patients with moderate dry eye, but of the two, the SH-containing treatment has marginal benefits in therapeutic efficacy and has less propensity to cause visual disturbance.