Treating pigmentary disorders

Las Vegas

- Treating tough pigmentary disorders requires combining current therapies while keeping abreast of emerging therapies including new sunscreens, resurfacing procedures and promising monotherapeutic bleaching agents, says an expert.

In treating difficult pigmentary disorders, such as melasma and postinflammatory hyperpigmentation (PIH), "The wave of the future will involve combination therapies. We have multiple agents that impact different pathways," says Pearl E. Grimes, M.D., director, Vitiligo and Pigmentation Institute of Southern California and clinical professor of dermatology, University of California, Los Angeles, David Geffen School of Medicine.

Therapeutic goals include stabilization, decreasing the contrast between hyperpigmented and normal skin and improving quality of life, she says.

Options that could help prevent pigmentary disorders include broad-spectrum sunscreen ingredients such as Mexoryl (ecamsule, L'Oreal), Tinosorb (CIBA) and Helioplex (Neutrogena), Dr. Grimes says.

In one clinical test involving 185 pregnant women who used a broad-spectrum sunscreen containing Mexoryl, titanium dioxide, octocrylene and avobenzone, only five new melasma cases occurred, which study authors say was significantly lower than the expected frequency of more than 50 percent in the study population (Lakhdar H et al. J Euro Acad Dermatol Venereol. 2007 Jul;21(6):738-42).

Combination bleaching agents include Tri-Luma (hydroquinone, tretinoin and fluocinolone, Galderma) and EpiQuin Micro (microentrapped hydroquinone and retinol, SkinMedica). Both products have shown efficacy in clinical trials, Dr. Grimes says.

As for the concern that long-term Tri-Luma use can cause epidermal atrophy, Dr. Grimes says a study she co-authored has shown no evidence of atrophy.

Additional bleaching agents with which dermatologists are gaining experience include kojic acid and azelaic acid, Dr. Grimes tells Dermatology Times.

New and emerging monotherapeutic agents for treating pigmentary problems include tyrosinase inhibitors such as rucinol, melanosome transfer inhibitors such as niacinamide, and resveratrol, which inhibits tyrosinase and COX-2 and scavenges reactive oxygen species, Dr. Grimes says.

Among resurfacing procedures, newer options include nonablative lasers and intense pulsed light (IPL) sources (including a new IPL source that controls pulse shape and distributes energy more evenly than its predecessors), as well as fractional laser resurfacing (Fraxel, Reliant Technologies), she says.

"Resurfacing procedures are key in my practice," Dr. Grimes says."We use them synergistically in combination with topical bleaching modalities."

However, she advises caution when using resurfacing modalities in darker skinned patients. DT

Disclosure: Dr. Grimes has performed clinical research for Allergan, Atlanta, Estella’s, Biogenic, Galderma, Named, Mary Kate, SkinMedica and Stiefel. She also is a consultant for Combe and GammaCan.