Norbloc, the ultraviolet blocker in Johnson & Johnson Vision’s ACUVUE Brand Contact Lenses, behaves as an antioxidant and provides a protective effect to a tear component that can be taken into the lens during wear, two studies showed.

In one study, researchers compared the antioxidant capacity of Norbloc to 10 known antioxidant compounds using Oxygen Radical Absorbance Capacity (ORAC) and found that the ORAC score was four times higher than vitamin E and was significantly higher than nine out of the 10 antioxidants tested.

In a second study, researchers compared silicone hydrogel lenses formulated with and without Norbloc using an experimental lipid model to determine how much a tear film lipid absorbed into the lenses oxidizes. After exposure to different doses of hydrogen peroxide and UV light, lenses that did not contain Norbloc showed statistically higher amounts of oxidative degradants compared to the lenses that did contain Norbloc.


Leave A Reply