Can you tell me are skin lightening creams safe for acne scars?

YES: Safe but not effective.

Safe, yes. : Skin lightening creams such as those with hydroquinone are generally safe to use on the face and can help blend skin that has a splotchy appearance in color. However, the cream is unlikely to help the scarring itself. That typically requires some sort of resurfacing procedure such as with a laser or dermabrasion. Using products with retin a (tretinoin) can help lightly resurface your skin.