A systematic review including 11 studies with a total of subjects was abstracted in DARE. Five of the 11 included RCTs reported adequate data to be pooled (three of which were high quality). Three used verbal pain scales and two used a VAS. The standardised mean difference suggested a statistically significant reduction in pain favouring treatment with topical NSAIDs (-0.52, 95% CI: -0.91, -0.13). When only the 3 high-quality trials were pooled (n=299), the standardised mean difference was -0.22 (95% CI: -0.45, 0.00). When the 3 RCTs (n=459) that used verbal pain scales were pooled, the overall weighted mean difference suggested a statistically significant reduction in pain favouring treatment with topical NSAIDs (-1.30, 95% CI: -1.56, -1.03, P<0.00001). Two trials reported that no adverse events occurred, while four reported that some patients experienced transient stinging with instillation of the eye drops. In one trial there were three recurrent corneal erosions: two in the control group and one in the NSAID group. In one trial a patient in the control group developed a corneal abscess and three patients in the NSAID group developed urticaria; since patients in this trial also received gentamicin, the cause of the urticaria was unclear.