Erythromycin eye ointment is a very commonly prescribed medication in ophthalmology. The price of this medication varies slightly depending on the manufacturer and generally ranges from$3-$10. The most commonly used price in hospitals is currently around$3.50. This drug is a kind of antibiotic eye ointment, so it can be used for the treatment of diseases caused by bacterial infections of the eye, including mydriasis, bacterial keratitis, conjunctivitis, etc. These diseases can be treated with erythromycin eye ointment. It is important to recognize when buying the drug, because there are two forms of this drug, the first is erythromycin eye ointment, this is used for the treatment of eye diseases. The second is erythromycin ointment, this is for dermatological use. The concentrations of these two drugs are different, so they should never be mixed.