Neomycin is an antibiotic. It is used to treat bacterial infections. Dexamethasone is a steroid. It is used to treat the inflammation associated with bacterial infections of the eye. Neomycin and dexamethasone ophthalmic is used to treat bacterial infections of the eyes. Neomycin and dexamethasone ophthalmic may also be used for purposes other than those listed in this medication guide.