Even with all my years of using glycolic acids, Retin A can still caused me irritation...but don’t let that stop you! It truly is the best product for seeing real results in sunspots, fine lines, etc. I had no issues using 0.025% nightly, but when I moved up to 0.5%, I noticed some peeling and flaking in some areas. I decided to try it over a light moisturizer instead of on a clean dry face. I wash with a gentle cleanser, being careful not to strip my skin, then apply a thin layer of Cerave PM. I usually put a heavier cream on my eyelids, and just under my eyes, apply emollient lip balm to protect my lips, then apply the Retin A as directed. Any peeling or flaking is so minimal it’s barely noticeable. I suppose I could just try using it only a few nights a week or every other night...but I like using it nightly, and the benefits are obvious and fast. Anyway, Retin A still works when applied over moisturizer, I’ve had more than one dermatologist tell me so.
I recommend starting with the lowest strength possible and working your way up to every day use. And sunscreen - VERY important. An SPF of 30 or higher, reapply as necessary, and stay out of the sun in general when you can avoid it. No point in using this stuff if you are going to continue to expose yourself to harmful sunlight, especially because using this will make your skin even more sensitive to the sun.