Does Mederma work on dark spots?

I need to get rid of dark spots caused by acne.And how quick does it work?Does Mederma work on dark spots?
I tried Mederma for the same thing once and I found it didn't really work. I went to my dermatologist and got a prescription for RetinA Micro and my dark spot went away completely. Now you can't even tell I had it.Does Mederma work on dark spots?
mederma can get rid of dark spots but it will take a very long time for it to work