A synthetic antioxidant similar to coenzyme Q10. Research for idebenone has not compared its effects to many of the hundreds of other potent antioxidants that commonly appear in other skincare products, nor did it compare the effects of idebenone with the effects of a combination of antioxidants. Perhaps a cocktail of antioxidants would far surpass idebenone—we don’t know. Other published studies compared the red grape antioxidant compound reseveratrol and L-ergothioneine to idebenone and found both superior to idebenone
To date, there are still no published, peer-reviewed studies that support idebenone’s alleged superiority. This does not mean idebenone is not a valid antioxidant for skin. Given what we know about how ubiquinone performs in the body, it is definitely not a throwaway ingredient. What is fairly certain, however, is that it is neither the best nor most potent antioxidant around.
References for this information:
Journal of Cosmetic Dermatology, March 2008, pages 2-7
Journal of Cosmetic Dermatology, September 2007, pages 183-188
The Journal of Investigative Dermatology, May 2006, pages 1185–1187