Treating severe eye allergy.

Allergic eye conditions, particularly seasonal allergic conjunctivitis (SAC), are common. Itching, oedema and hyperaemia are relieved with topical H1-antagonists or sodium cromoglycate. The newer mast-cell stabilizing agent nedocromil sodium has a similar safety profile to sodium cromoglycate, but is more potent and has a more convenient twice-daily dosing regimen. When several placebo-controlled studies of its use in the treatment of SAC were analysed, it was found that 80% of patients reported symptom relief. In a further study, nedocromil sodium eyedrops (twice-daily dosing) had similar overall efficacy to sodium cromoglycate eyedrops (four-times-daily dosing) in subjects with SAC during the birch season, but during the period of highest pollen challenge, only the former agent was significantly more effective than placebo. Another study found that nedocromil sodium had efficacy equivalent to levocabastine over 7 days, but tended to have a more rapid onset of action. In patients with perennial allergic conjunctivitis (PAC) unresponsive to sodium cromoglycate, both clinicians and patients reported significantly better control of symptoms with nedocromil sodium eyedrops than with placebo. Recently, in a long-term study of treatment for vernal keratoconjunctivitis (VKC), it was found that nedocromil sodium 2% eyedrops produced a more rapid and marked improvement in symptoms than sodium cromoglycate 2% eyedrops and enabled lower use of steroid rescue medication. Both drugs were well tolerated and without serious side-effects.