Comparison of Tobramycin-Dexamethasone Combination Eyedrop Versus Artificial Tear Eyedrop for the Management of Presumed Viral Epidemic Conjunctivitis: A Randomized Treatment Trial.

Purpose: To compare the efficacy and safety of one-time povidone-iodine (PovI) administration followed by a course of tobramycin-dexamethasone eye drops versus artificial tears in acute viral conjunctivitis (AVC).

Methods: This was a single-centre, randomized controlled trial. Patients with AVC were instilled with PovI (5%) after proparacaine and then divided into two groups using a computer-generated random number table. Group A received combination drops of tobramycin(0.3%) and dexamethasone(0.5%), and group B received carboxymethylcellulose(0.5%) eyedrops. Both groups administered one drop four times daily for at least three days and until complete symptom resolution. A symptom score (SS) encompassing the five symptoms (redness, lid swelling, foreign body sensation, pain, watering; max score 15) was calculated at baseline, day 3, and day 7.

Results: The study included 230 eyes (120 in group A, 110 in group B). There was a significant reduction in mean total SS at day 3 (2.16 ± 2.42) and day 7 (0.56 ± 1.14) in all eyes compared to at presentation (8.33 ± 2.46). At day 3, there was a lower mean total SS in group A (1.97 ± 2.31) compared to group B (2.36 ± 2.54) which was marginally significant (p = 0.086). At day 7, the proportion of eyes that were symptom-free was similar between groups (70.9%, p = 0.881). A multivariate analysis found that group B (OR = 2.08, p = 0.036) and a higher pain score (OR = 1.50, p = 0.046) were associated with a lack of clinical resolution by day 3.

Conclusion: A course of tobramycin-dexamethasone combination eyedrops after PovI may lead to early symptomatic relief, but recovery was similar to artificial tears by day 7. No significant/sight-threatening complications were observed in any groups.