In recent years, there have been increased efforts to find safer and effective drugs to treat various ocular conditions as well as to develop novel dosage forms and delivery systems to improve the topical delivery of existing drugs. Today, topical ophthalmic application is considered the preferred way to achieve therapeutic levels of the drug used to treat ocular diseases. The conventional preparations for this route fall into several categories: solutions, suspensions, semisolids and others. Bioavailability, particularly for ocular solutions, ranges from 1 to 10% of the total administered dose. Oily eye drops can be used for three reasons namely to produce an emollient effect, to protect a compound liable to hydrolysis and to obtain an enhanced effect. Some drugs are broken down in an aqueous solution and are supplied as oily drops to prevent this. Some drugs are broken down in an aqueous solution and are supplied as oily drops to prevent this. Since, lipophilic substances cross the epithelial barriers more easily than hydrophilic ones, it would appear logical to provide drugs in the former state rather than the later. Topically applied agents produce effective levels mainly in the anterior segment. As far as the optometrist is concerned, the topical route is the only one that is applicable.