The two major forms of OSD are dry eye and blepharitis. These conditions tend to alter the tear film and may cause a noticeable degradation of vision and irritation to the front surface of the eye. Depending on the severity, a limitation in the clarity of eyesight may result in an increased risk of secondary infection or chronic inflammation that is resistant to treatment. Common eye complaints include burning and/or stinging, scratchiness, tearing, increased mucus and reduced contact lens tolerance if applicable. As OSD is clinically challenging educating patients about dry eye and blepharitis is an important element in successfully controlling these ocular problems.