At first, there were no problems using the product according to the instructions. It took maybe two months before I noticed results. I felt very positive then, but since then I have gotten swollen eyelids, itching, and skin peeling around the eyes from the product. At first, I thought it was a common eye infection since I also had blurry vision and such symptoms. I paused, let the inflammation heal, and tried the serum again yesterday, resulting in itching, swelling, and redness. So unfortunate!