Can a Person Change His or Her Skin Color?

You are not referring to a bleaching cream but a lightening cream. Lightening creams have hydroquinone a chemical that has been questioned about its safety, one that can cause irritation, and rarely in some people a paradoxical darkening caused by a deposition of chemical product in the dermis called ochronosis. It is against the standard of care to apply this cream over a wide surface area such as the arms and legs. There really is no good way to lighten the skin tone two or three shades.... more

There are numerous skin bleaching agents but this potentially has adverse effects, given the amount of product required. The primary active ingredient is hydroquinone but it's effect can be enhanced by the use of retinoids.  I'm assuming you are speaking about making it lighter. There was a non-fiction story entitled "Black Like Me" about an inidividual who made his skin appear darker.