Hydroquinone is a controversial ingredients for skin bleaching. It inhibits the production of tyrosinase,
an enzyme integral to the production of melanin. Hydroquinone has been banned in several countries and is currently
the focus of a proposed U.S. Food & Drug Administration rule that seek to remove the ingredient from over the counter
formulations in the United States.
There are three charges leveled against hydroquinone. The first is that it's a cancer-causing agent. The second
is that it's cytotoic, which means that rather than suppress melanin production, the ingredient has a toxic effect on cells
and can actually destroy melanocytes. This tends to occur in dark skin types with long-term use. The patient ends up
with a white ring on her skin where melanin is no longer being produced.
The third, and perhaps the most compelling, is exogenous oxhronosis. This is a potentially permanent and disfiguring
skin condition where pigmented spots darken to become blue-black in color.
There are alternatives. Natural quinones include bearberry, mulberry, licorice extract, cedar, arbutin and kojic
acid. These ingredients have a a long history. Research in Asia has shown that paper mulberry bark, for example,
is as strong as hydroquinone, yet doesn't have the same irritation factor.
The number one cause of hyerpigmentation is photo damage. The best thing you can do to prevent it is use sun
screen. The darker the skin, the deeper the discoloration and the more difficult it is to treat. Prevention is
key.
