Retinol and Vitamin C at the same time?

Vitamin C serums are most effectively utilized in the AM for optimal protection against environmental damage caused by free radicals. SkinCeuticals C E Ferulic is a synergistic antioxidant combination of 15% pure vitamin C (L-ascorbic acid), 1% vitamin E (alpha tocopherol), and 0.5% ferulic acid.  We recommend Retin-A as a PM treatment and follow with SkinCeuticals Triple Lipid Restore 2:4:2. This moisturizer shortens the adjustment period to retinoids up to 1 week while reducing dryness. In an 8-week clinical study, Triple Lipid Restore 2:4:2 significantly improved the appearance of key visible signs of accelerated aging.

I recommend CE Ferulic by SkinCeuticals as it is the most tested Vitamin C on the market. It is also stabilized, while many Vitamin Cs on the market aren't. All of that being said it is not helpful to apply at night. It helps protect your skin from environmental factors which occur during the day, not the night. It will be a waste for you to apply it at night."This answer has been solicited without seeing this patient and cannot be held as true medical advice, but only opinion. Seek in-person treatment with a trained medical professional for appropriate care."