There are three main types of post-acne signs. Brown spots, pink spots, and real acne scars—also referred to as "ice-pick," "boxcar," or "rolling" scars. 

     Pink Spots: Post acne pink spots are caused by dilated skin capillaries and will
     usually fade away on their own within about 2-3 months (once the active acne is
     controlled). 

     Brown Spots: Some of these will also fade with time. That said, you can fade them
     more quickly with the MDacne Medicated Dark Spot Remover. If you still have
     active acne, you would be able to apply it on alternate nights with your acne
     treatment cream. 

     Real Acne Scars: "Real" acne scars are more complicated to treat—moisturizers
     and creams won't do much for with these. That said, there are minimally invasive
     treatments (like micro-needle RF and lasers) that are available in most
     dermatologists' offices that can help. 

Check out this link for info on how to treat acne scars!