In a group of 46 people, Dr. Antoine Petit of the Hopital Saint Louis, Paris and colleagues identified two with insufficient adrenal gland function that was likely due to use of one product called clobetasol, which is illegal in France.

Others had hyperpigmentation, stretch marks, skin atrophy (degeneration) and infections that could have been related to use of skin lightening products, while many reported being unable to stop trying to lighten their skin even though they wanted to.

"This particular feature of skin lightening is akin to addictive behavior, sometimes associated with real psychological suffering," Petit and colleagues write in the Journal of the American Academy of Dermatology.

Skin lightening appears to be a common practice among dark skinned individuals in most of the world, and has been linked to side effects ranging from disfiguring scarring to system-wide health problems, the researchers note. However, they add, there have been few reports on complications due to use of these products from industrialized nations such as France and the United States.

To investigate, Petit and colleagues examined 46 patients of African descent who had changes in their skin that could have been due to use of skin lightening products. These included excessive darkening of the skin on the finger joints, atrophy of the skin, stretch marks and infections.

Twenty five of the men and women in the study reported using skin lightening products, 12 said they were attempting to stop using the products, 7 said they had used them in the past but no longer did, and two said they had never used the products.

On average, people reported having used skin lighteners for 14 years, with time of use ranging from one to 38 years.

All people who reported lightening their skin said they had used at least two products in combination, generally glucocorticoids (use of which could theoretically lead to diabetes and high blood pressure), hydroquinone, or clobetasol.

Nine people referred to skin lightening as a "true drug," while many reported having difficulty stopping the use of these products even if they were unsatisfied with their effects. Frequently patients would look for more powerful products to cope with the hyperpigmentation side effects they experienced.

While some participants in the study did have high blood pressure and diabetes, it was impossible to determine if it was due to the use of skin lightening products. But the researchers did find two cases of adrenal insufficiency that they attributed to clobetasol use, noting that people in the study used up to 480 grams weekly, while 50 grams weekly is enough to affect adrenal gland function.

"There is an urgent need to inform dark-skinned persons of the nature and side effects of the products used for skin lightening, especially clobetasol," the researchers conclude.

"Clinical as well as epidemiological and psychological aspects of skin lightening deserve further studies to improve the prevention and management of skin lightening side effects."

SOURCE: Journal of the American Academy of Dermatology, November 2006.

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