Developing an erythromycin ophthalmic ointment: putting the puzzle pieces together

With the development of new treatment options and reported side effects with the use of silver nitrate ophthalmic solution, the drug manufacturers discontinued production of the silver nitrate ophthalmic solution in the mid-1990s. On December 9, 2009, the U.S. Food and Drug Administration announced that the erythromycin ophthalmic ointment 1-gram tubes were commercially available again and production by the manufacturer was expected to meet the historical demands. Hospitals could expect to replenish their inventory reserves after the first quarter of 2012. However, manufacturer backorders have been increasing due to a variety of factors. If a hospital has a compounding laboratory, it is possible to prepare erythromycin ophthalmic ointment according to the United States Pharmacopeia Chapter 797 standards. Since the commercial product has been available for decades without any major shortages until 2009, there isn't any published compounding information on how to prepare the ointment. This article discusses the development of a new procedure to compound erythromycin 0.5% ophthalmic ointment, the compound of which may be useful in any future shortages. Compounding can involve some intensive research in order to create a new formulation, especially when the compounder does not have access to a hired technical support service. It can be very challenging, but as this article explains, it is not impossible to do.