An analysis of contact lens enzyme cleaners

Currently, in the United States, the Food and Drug Administration has approved a number of enzyme cleaners for use with soft contact lenses. These cleaners contain three active enzymes--papain, pancreatin, and subtilisin. Although several studies have compared the cleaning efficacy of papain and pancreatin, little information exists concerning subtilisin. It was the aim of this investigation to compare the performances of four marketed enzyme cleaners, including Allergan Enzymatic (papain), Optizyme (pancreatin), ReNu Effervescent (subtilisin), and Ultrazyme (subtilisin A). Lenses were examined using the scanning electron microscope, and the amount of deposits on the lens surfaces quantified by digital analysis. All of the enzyme cleaners were effective in removing deposits from the contact lenses surfaces, but there was no significant difference in the cleaning efficacy of the four cleaners tested.