Does the higher strength of tretinoin (Retin A) really make a difference?
I think it’s probably just the irritation from it. It takes 30-90 days to really see a difference in fine lines due to an increase in collagen. There may not be much benefit from using the higher concentrations of tretinoin (Retin A/Renova) over the long term. Since it causes more irritation, I generally advise my patients to stick with the 0.025 or 0.20% because they will use it more consistently. Dr. I