Go gently at first
I really love this product, but I had to scale back after the first 2 weeks. I also have to avoid my lower neck area, because my thin skin will develop a rash there. Be very careful around eye area because the acid in the product will burn if one gets it in the eye. I now use Cellex-C in the morning only. I also wait about 7-8 minutes before applying any other product such as moisturizer or makeup. I definitely see improvement in my skin.