Hydroquinone is an effective ingredient in skin bleaching cream that is used to treat and fade liver spots, melasma, freckles, acne scars and other skin discolorations. There is some dispute over whether hydroquinone is completely safe to use or not. The FDA has placed a concentration limit of 1.5 to 2% on over the counter formulations because of evidence that it may cause cancer if ingested. More research is required since this carcinogen designation was based on mice and rodents and was at fairly high concentrations. Dermatologists have stronger concentrations available via prescription than those available over the counter. That said, it’s important to follow the directions when using these products.