Does retinol a work well on acne scars?

No: It is a mild way of inproving fine lines but it can also thin the skin and make you at higher risk for sun burn or sun damage. When used alot after age 45 it can cause thinning of the skin. Retin a (tretinoin) is very helpful for active acneic breakouts when applied at bedtime using a thin layer.

Retin A=>Prevention: It won't help existing acne scars, if there are indentations and irregularities on the surface of the skin. However, it does help reduce acne breakouts in general, and is one of the fda approved uses for retin a (aka tretinoin.) redness and blemishes after an acne breakout without a scar will usually resolve on its own, and would not really be considered an acne scar.