Topical Non-Steroidal Anti-Inflammatory Drugs in Allergic Conjunctivitis: Meta-Analysis of Randomized Trial Data

Purpose: To assess the effect of topical Non-Steroidal Anti Inflammatory drugs in the treatment of allergic conjunctivitis. Method: Systematic Review. Data Sources and study selection: Reports of comparative randomized trials of topical NSAIDs and placebo identified by searches of Medline, Embase, the Cochrane Register of Controlled Trials. Data extraction and synthesis: Two reviewers assessed trials for eligibility and quality and extracted data independently. Data were synthesized (random effects model) and results expressed results for dichotomous outcomes as relative risk and continuous outcomes as weighted mean difference. Sensitivity analysis was used to examine potential heterogeneity by differences in study quality. Results: Eight studies incorporating 712 patients were included. The difference between the decrease in allergic sign and symptom score for NSAID treatment compared to placebo was between 4 and 19 percentage points. Topical NSAIDs produced significantly greater relief for conjunctival itching (cardinal symptom) than did placebo (combined standardized mean difference −0.54 (p < 0.001; 95% confidence interval −0.84 to −0.24). The results for the other allergic symptoms: ocular burning/pain, eyelid swelling, photophobia and foreign sensation were not significant. Topical NSAIDs produced significantly greater reduction of conjunctival injection than did placebo (combined standardized mean difference −0.51 (p = 0.03; 95% confidence interval −0.97 to −0.05). Topical NSAIDs did not reduce the allergic signs of conjunctival chemosis, conjunctival mucus, eyelid swelling and corneal disturbance. Topical NSAIDs had a significantly higher rate of burning/stinging on application of medication compared to placebo (P < 0.0001; odds ratio 3.97 (95% CI 2.67 t0 5.89). Conclusion: This meta-analysis confirms that topical NSAID are significantly more effective at relieving the cardinal symptom: conjunctival itching and improving the cardinal sign: conjunctival injection than placebo treatment. A systematic review comparing topical NSAIDs to topical antihistamines/mast cell stabilizers in treatment of allergic conjunctivitis is warranted as this will compare the topical NSAIDs to current therapeutic guidelines.