Analgesic Effect of a Single Drop of Nepafenac 0.3% on Pain Associated with Intravitreal Injections: A Randomized Clinical Trial.

PURPOSE: To evaluate the analgesic effect of nepafenac 0.3% in patients undergoing intravitreal injections (IVI) of antivascular endothelial growth factors.

METHODS: This is a single-center, prospective, randomized, blinded, triple-arm, placebo-controlled interventional study. Patients were randomized into 3 Groups. Group 1 (n = 33) received nepafenac 0.1%, Group 2 (n = 32) received nepafenac 0.3%, and Group 3 (n = 31) received placebo 40 min before IVI. Using the short form of the McGill Pain Questionnaire (SF-MPQ), pain intensity was assessed with the visual analog scale (VAS), the Main Component of the SF-MPQ, and the present pain intensity (PPI) scores immediately and 6 h postinjection.

RESULTS: Immediately after IVI, the VAS pain score was statistically significantly lower in patients treated with nepafenac 0.1% and 0.3%, compared with placebo (P < 0.001 and P = 0.001, respectively). The PPI scores were statistically significantly lower when nepafenac 0.1% or 0.3% was instilled compared with placebo (P = 0.01 and P < 0.0001, respectively). The Main Component of the SF-MPQ scores were statistically significantly lower after nepafenac 0.1% and 0.3% administration compared with placebo (P = 0.001 and P < 0.001, respectively). Six hours post-IVI the nepafenac 0.3% demonstrated statistically significantly higher analgesic effect compared with nepafenac 0.1% and placebo as this was indicated by the VAS pain score (P = 0.013 and P < 0.00001, respectively) and by the PPI score (P = 0.01 and P < 0.00001, respectively).

CONCLUSIONS: A single instillation of nepafenac 0.1% or 0.3% before IVI could effectively alleviate the IVI-related pain. The 0.3% formula exerts its analgesic effect more intensively at 6 h after the IVI.