Cleaning/Disinfection Options Studies show that up to 80% of contact lens complications are caused by improper cleaning and disinfection. Without proper care, protein deposits, dirt, debris and microorganisms build up on the lens and increase the risk of injury to the eye and infections, including those that can cause blindness. This section summarizes the three most common cleaning and disinfection options used today for soft contact lenses: multipurpose solutions, hydrogen peroxide systems, and multi-step systems. Unlike the PuriLens System, these options use chemicals and preservatives that may be absorbed by the lens or irritate sensitive eyes. The simple to use PuriLens System makes cleaning and disinfecting automatic, reducing the risk of infection caused by not following the recommended lens care procedures. Chemicals and Preservatives Found In Lens Care Products The table below lists some of the common chemicals found in contact lens cleaning solutions. Compare the list to solution you currently use. If you are experiencing any discomfort with your lenses, the chemical-free PuriLens System may be the solution for you. Chemical/Preservative Comments Thimerosal concentrations of 0.001% to 0.2% used in combination with other preservatives may cause sensitization in some individuals may bind to debris on soft lenses Chlorhexidine usually used in combination with other preservatives precipitated by borates, phosphates and carbonates may irritate the eyes degradation products can cause yellow-to-green coloration Sorbic acid (or potassium sorbate) commonly used in solutions for soft contact lenses toxic or allergic reactions are rare - less toxic than some other preservatives may cause age dependent yellow to browning of some lenses exhibit weak activity at physiological pH polyquaternium-1 (Polyquad) can be used with soft and hard contact lenses toxic or allergic reactions are rare - less toxic than some other preservatives Hydrogen peroxide disinfects soft lenses can irritate or burn the eye if not properly neutralized Polyaminopropyl biguanide disinfects soft lenses Adapted from Drug Store News, June 28, 1999