"First of all, I'd like to say that I bought this to treat my persistent hormonal acne. I have PCOS, and one of its "lovely" symptoms is persistent acne. Previously, I was using Obagi benzoyl peroxide serum, which was great, but always dried my skin and left me with deep under the skin cystic type acne. I read online that benzoyl peroxide can do that and actually age the skin, so I wanted to try SkinCeuticals Retinol 1.0 Cream. The first 2 weeks were awful, which I expected from what retinol can do. I felt like my skin was shedding. More pimples came up and I looked worse than before, but I think my skin was purging all the bad stuff out. On week three, all the flaky-ness is gone. My skin is smooth now, and still healing. The discoloration of the past acne are slowly going away and so far I'm happy at the end of week 3 and going on week 4!"

"I have been using a retinol product for over a year so my skin is quite conditioned, however have never used a maximum strength. I have had no side effects at all from using this product every single night. Some slight peeling that was easily removed with an alpha hydroxy acid toner. I used other products but am careful not to 'mix' them with this one as that is when irritation is most likely. My skin is very refined and smooth to the touch. My acne also responds very well to a retinol treatment. The only thing I can advise is that the bottle says use a pea sized amount, I would advise to rather pump and apply as it's not easily spreadable so it easy to miss spots if you pump out one pea size and expect it to cover the whole face. Also do not use on your neck unless that is conditioned to retinol."