Combination therapies do battle with ethnic pigmentary problems

Sep 01, 2004, 4:00am

New York and Pennsville, N.J. - While hydroquinone remains crucial for treating pigmentary disorders in ethnic patients, the most effective treatments frequently combine this drug with other preparations and treatment modalities.

New York and Pennsville, N.J. - While hydroquinone remains crucial for treating pigmentary disorders in ethnic patients, the most effective treatments frequently combine this drug with other preparations and treatment modalities.

"The differential diagnosis of pigmentary disorders is vast," says Fran E. Cook-Bolden, M.D., assistant clinical professor in Columbia University's dermatology department. "It can encompass genetic, nutritional, endocrine and neoplastic or cancer problems. But by far the most common pigmentary disorder in ethnic patients is post-inflammatory hyperpigmentation (PIH), followed by melasma."

Virtually any inflammatory process or skin problem such as acne or eczema can cause PIH.

As for treatments, hydroquinone has been the mainstay for more than 50 years.

"It still remains the basis of therapy," Dr. Cook-Bolden says. "However, in recent years, there's been a revolution of combination hydroquinone therapies that include things like glycolic acids, retinoids, antioxidants and sunblocks. Right now, the best and most effective treatments are the combination treatments."

Sunblock is primary protection The first line of defense against PIH and other pigmentary disorders in patients of color is sunblock.

"Traditionally," she says, "many people of color are not taught to use sunblocks, although today, patients are very savvy. They know that it's important to use sunblocks, not only to prevent skin cancer or photo-damage, but also to achieve success at clearing up dark marks or preventing their worsening. What a lot of people of all skin types don't know is the proper way to use sunblocks and what to look for in a sunblock. Probably one of the most important things you need to do is to reapply it every two hours if you're going to have continued sun exposure or re-exposure."

Role of azelaic acid Azelaic acid also plays a role in battling PIH. It's a chemical produced by a fungus that can cause tinea versicolor.

"Clinically, patients with pityriasis versicolor initially present with tan or brown spots. Subsequently, they often develop white spots and the entire affected area can turn white. Azelaic acid is the component that causes those areas to turn white via reversible inhibition of tyrosinase," Dr. Cook-Bolden says.

As a medication, azelaic acid is U.S. Food and Drug Administration (FDA) approved for treating acne and especially helpful for treating acne with discoloration.

"It's often more effective as a lightening agent than a 'solo' acne agent," she says.

Natural ingredients popular Creams containing natural ingredients such as blueberry, boysenberry and licorice also are gaining popularity, though there's little research behind them. Likewise, many cosmeceutical preparations now contain kojic acid and arbutin.

"There's been more research done on kojic acid and arbutin. Arbutin is a naturally-occurring plant derivative which is found in Phytocorrective Gel (Skinceuticals)," says Dr. Cook-Bolden. "They do indeed appear to have some efficacy in terms of lightening dark spots."

Combination therapies Other agents used in combination therapies include tretinoin and retinols, glycolic acid and topical steroids. The latter can help prevent irritation from hydroquinones and tretinoins while possessing intrinsic lightening properties.

"There are several very effective hydroquinone combination prep-arations now available that are far superior to what we've had in the past," she says.

Examples in this area include Tri-Luma Cream (Galderma) and Solage (Galderma) (fluocinolone acetonide .01 percent, hydroquinone 4 percent, tretinoin .05 percent and mequinol 2 percent, tretinoin .01 percent, respectively); EpiQuin Micro (Skin Medica), whose microsponge encapsulation provides continuous release of the hydroquinone-retinol combination; Glyquin XM (Valeant Pharmaceuticals), which includes glycolic acid; and Claripel (Stiefel Laboratories), which includes a sunblock.