Abstract
Purpose: :
Diclofenac, a widely used topical non-steroidal anti-inflammatory drug (NSAID), has an analgesic effect on the cornea. Different NSAID eye drops may have differing analgesic effects on the cornea. The authors evaluated nepafenac (Nevanac) and bromfenac (Xibrom) to determine their analgesic effect on normal adult eyes.
Methods: :
In a prospective study, 30 patients were randomly assigned to receive either (1) placebo or nepafenac in each eye or (2) placebo or bromfenac in each eye. Patients were divided into 3 groups: Group A composed of 30 patients who received placebo, Group B composed of 15 patients who received nepafenac and Group C composed of 15 patients who received bromfenac. A Cochet-Bonnet aesthesiometer was used to test corneal sensation at baseline, prior to administration of any drops, and at 1 minute, 10 minutes and 30 minutes after instillation of placebo or medication.
Results: :
Baseline corneal sensitivity for Groups A, B and C had mean of 58.3 (SD=3.56). Group A (placebo) at 1 minute had a mean sensation of 53.3 (SD=8.84), at 10 minutes a mean of 54.7 (SD 8.90) and at 30 minutes a mean of 55.5 (SD=8.23). Group B (nepafenac) at 1 minute had a mean sensation of 53.3 (SD=10.97), at 10 minutes a mean of 56.7 (SD=6.17) and at 30 minutes a mean of 56.3 (SD=4.81). Group C (bromfenac) at 1 minute had a mean sensation of 54.7 (SD=9.15), at 10 minutes a mean of 52.7 (SD 10.33) and at 30 minutes a mean of 53.3 (SD=7.94). All results were analyzed using a Student’s T-test. Group A (placebo) showed a statistically significant reduction (p<0.05) in corneal sensitivity at 1 and 10 minutes but not at 30 minutes when compared to baseline. Group B (nepafenac) did not show a statistically significant reduction in corneal sensation whether compared to baseline or to Group A (placebo) at any time point. Group C (bromfenac) showed a statistically significant (p<0.05) reduction in corneal sensitivity at 30 minutes when compared to baseline measurement of corneal sensation. Group C (bromfenac) did not show a statistically significant reduction in corneal sensitivity when compared to Group A (placebo). Group C (bromfenac) showed a trend towards reduction in corneal sensitivity at all time points when compared to Group A (placebo).
Conclusions: :
The placebo showed analgesic effect at 1 and 10 minutes. Nepafenac did not have an analgesic effect when compared to baseline or to placebo at any time point. Bromfenac did have a potential analgesic effect at 30 minutes when compared to baseline and showed a trend towards reduction in corneal sensitivity at all time points when compared to placebo.
Keywords: cornea: clinical science • inflammation • ocular irritancy/toxicity testing