Effects of nedocromil sodium on antigen-induced conjunctivitis in guinea pigs

We evaluated nedocromil sodium in a guinea pig model of allergic conjunctiv itis. Ten days after the animals were passively sensitized to ovalbumin, ne docromil sodium (2 mg) or normal saline was instilled into the conjunctival sac, followed by antigen challenge with ovalbumin (100 mu g or 300 mu g/10 mu L). Conjunctival hyperemia, edema, and eyelid edema were evaluated at 1 0 minutes and 4 hours in the 100-mu g ovalbumin group. Eyes with nedocromil sodium exhibited fewer early and late clinical signs of allergic conjuncti vitis than control eyes. Infiltrating eosinophils were counted at 24 hours in the 300-mu g ovalbumin group. Nedocromil sodium inhibited antigen-induce d eosinophil infiltration into the limbus, fornix, and eyelids by 77%, 66%, and 74%, compared with controls. Nedocromil sodium can effectively suppres s early- and late-phase conjunctival hyperemia, conjunctival edema, eyelid edema, and eosinophil infiltration in the guinea pig passive-sensitization model. Nedocromil sodium may represent a ver satile option for the treatmen t of allergic conjunctivitis.