Is the dermatological boon a danger to patients?
DERMATOLOGY As we age, a battle to maintain the smooth and supple skin we were born with begins. We combat hyperpigmentation from acne, ingrown hair, sun damage, scars, freckles, age spots and melasma. Skin darkening may be influenced by gender, trauma, genetics or hormonal changes.
With such an onslaught of skin attacks, dermatologists are often tasked to even out mottled complexions. Some dermatologists may routinely prescribe hydroquinone, which has been considered one of the most effective skin lightening agents for many years.  But there are important facts to consider before use.
The Dark Side of Hydroquinone
The U.S. Food and Drug Administration (FDA)-approved prescription drug skin-lightener, hydroquinone (up to 4 percent), was grandfathered into acceptance because it was widely used to impede melanin production before inception of the FDA. Paradoxically, in 2006 the FDA proposed an unenforced U.S. ban on OTC sales of cosmetic products containing up to 2 percent hydroquinone. This was based largely on a 1994 report published by OSHA in the Journal of the American College of Toxicology (now known as the International Journal of Toxicology). Preliminary findings indicated, "hydroquinone is mutagenic and has cancer-causing potential." The OSHA addendum stated that "hydroquinone is a potent cytotoxic agent that causes mutations and alterations to DNA, and that it should not be used in any leave-on type of product; it is safe for rinse-off products when used in concentrations less than 1%." Because of its cytotoxic impact on the melanocyte within the skin, it is said to disrupt basic cellular processes, including DNA and RNA synthesis. [2,3] Europe, Asia and several African countries have enforced strict guidelines on hydroquinone use.
With lack of FDA approval, alternatives to hydroquinone cannot be labeled skin-lighteners or whiteners, so the industry often uses the term "brightener." They range from preparations with various hydroxy acids to red algae. The newest agents to fight melanin formation are the peptides, which appear to brighten sun-induced hyperpigmentation in half the time of other skin brighteners.
Challenges of Hydroquinone
Within the skin, melanin regulates pigmentation with racially based differences. It is more difficult to lighten skin in individuals with darker complexions due to the enhanced ability of darker skin to produce melanin. Post-inflammatory hyperpigmentation occurring from skin trauma in dark-skinned individuals is a challenge because skin lighteners must penetrate deep within the stratum basale. More visible pigmentation is evident among people with lighter skin. Yet, over-the-counter (OTC) skin-brighteners are more successful among this population. 
Mitigating the Effects of Hydroquinone
As might be expected, higher doses of hydroquinone generally produce more rapid results. Hydroquinone can also irritate the skin of some people, triggering redness or more severe pigmentation called onchronosis. Initial use is therefore recommended in a small inconspicuous area.
Treatment involves a juggling act to lighten pigmentation, stop future sun damage, suppress inflammation (usually with cortisone)  and even out skin tone. Ideally, damaged skin is exfoliated, new skin is protected from tanning and melanin is inhibited. Large areas of hyperpigmentation seldom lighten uniformly with hydroquinone. During treatment, patches of lightened skin may appear among darker areas. This can trigger additional emotional issues. Patients may be urged to seek non-irritating opaque cosmetics with UV inhibitors.
The sun emits visible light along with invisible ultraviolet-B (UVB) and -A (UVA) radiation. Sunburn is caused by UVB radiation. (Think "B" for "burn.") Skin tanning (melanin darkening) is caused by UVA radiation. Preventing sun damage through application of UVA sunscreens is fundamental.  In fact, sunlight dramatically reduces the effects of hydroquinone.
As discussed thus far, complete hydroquinone skin lightening care includes deep cleansing, skin lightening, an anti-inflammatory drug, UV protection and possibly hypoallergenic cosmetics. A complete course of treatment can take 4 to 12 months. Discontinuing product use or providing a rest for skin may be recommended if results are not observed within an established period of time.
Complex subdermal chemical changes are triggered by hydroquinone. Often it is combined with other ingredients to enhance penetration, reduce sun damage, or minimize irritation. In light of potential complications, it seems prudent to pursue hydroquinone use only under the care of a qualified physician or inquire about alternative treatments such as exfoliation and dietary changes. 
In the face of concerns over hydroquinone, it does not have to be prescribed by a physcian or accepted by a concerned patient. There are many skin lightening alternatives — both natural and prescription — available.
- Draelos Z, Hydroquinone: Is the Cure Worse Than the Problem? Skin Inc, March 2009
- Stoppler M, FDA Proposes Hydroquinone Ban. MedicineNet.com, August 2006
- Draelos Z, Skin-lightening Challenges. Skin Inc, January 2009
- How to Treat Hyperpigmentation with Hydroquinone. eHow.com
- Mark S, How to Lighten Skin Naturally. HubPages.com
- Skin Bleaching Alternatives to Hydroquinone: Medical Comparisons of Their Effectiveness. American Chronicle, americanchronicle.com, January 19, 2007
- Benefits of Cocoa Butter on Scarring. LiveStrong Foundation, livestrong.com
- Retin-A. Drugs.com