Comparative Efficacy of Polyethylene Glycol with Propylene Glycol Versus Sodium Hyaluronate in Mild Epidemic Keratoconjunctivitis: A Randomised, Double-Masked Clinical Trial

Objective: To compare the efficacy of preservative-free polyethylene glycol 0.4% with propylene glycol 0.3% (PEG/PG) versus 0.1% sodium hyaluronate (HA) tear substitutes in patients with mild epidemic keratoconjunctivitis (EKC). Methods: This prospective, randomised, double-masked, parallel-group trial enrolled 48 patients (96 eyes) with mild EKC. Patients were randomised 1:1 to receive either PEG/PG ( n = 24) or HA ( n = 24) four times daily for 14 days. The primary endpoint was patient-reported comfort score (1–5 scale) at day 14. Secondary endpoints included conjunctival redness, discharge and clinical improvement rates. Outcomes were assessed at baseline, day 7 and day 14 using non-parametric statistical methods. Results: Both groups showed no significant baseline differences in comfort ( P = 0.4657), redness ( P = 0.2465) or discharge ( P = 0.4028). Both treatments produced significant improvement from baseline ( P < 0.001). However, HA demonstrated superior reduction in conjunctival redness at day 14 (median 0.0 vs 0.2, P = 0.0074). Clinical improvement rates for comfort ≥4 were high in both groups (PEG/PG 91.7%, HA 95.8%). Complete resolution of redness was significantly higher with HA (83.3% vs 50.0%). Conclusions: Both tear substitutes effectively improved comfort in mild EKC patients. While patient-reported comfort was equivalent, HA demonstrated superior efficacy in reducing conjunctival redness, suggesting potential advantages in controlling the clinical signs of EKC.