Comparison of effects of topical levocabastine and nedocromil sodium on the early response in a conjunctival provocation test with allergen☆☆☆★★★

Abstract 

BACKGROUND:Multiple ocular challenges or seasonal trials have demonstrated the efficacy of levocabastine and nedocromil sodium in the treatment of allergic conjunctivitis. OBJECTIVE: This study was designed to compare the protective effect of levocabastine eye drops with that of nedocromil in a conjunctival provocation test with allergen. METHODS: Twenty-four patients with allergic conjunctivitis to grass pollen were recruited. After a preliminary provocation to determine conjunctival reaction threshold (erythema of at least 50% of the conjunctiva with ocular itching), patients were randomized to receive either topical levocabastine (0.05%) or nedocromil (2%) 15 minutes before provocation. Erythema and pruritus intensity were recorded at each concentration of allergen up to the reaction threshold. RESULTS: The allergen concentration level necessary to reach reaction threshold was increased (p < 0.001) after treatment with both drugs. Comparison between screening and each treatment indicated that the shift in allergen concentration was significantly greater after levocabastine treatment than after nedocromil treatment (p = 0.019). Conjunctival itching (symptom score) and erythema (percent conjunctival surface) were also better controlled by levocabastine than by nedocromil during provocation (p < 0.05). CONCLUSION: In a provocation test with allergen, levocabastine and nedocromil were both effective in increasing the conjunctival tolerance to allergen, with better protection provided by levocabastine. (J Allergy Clin Immunol 1996;98:1045-50.)

Keywords:  Levocabastine, nedocromil sodium, allergic conjunctivitis, allergen challenge, provocation test

Abbreviations:  BU: , Biologic units, PBS: , Phosphate-buffered saline