Lightening up: Other options

But rating the relative effectiveness of substitutes - including an ever-expanding array of topical preparations and dietary supplements - proves nearly impossible for many reasons, experts say.

Formulation also impacts effectiveness.

"Cosmetic companies are loath to test their products against each other" for fear of being outperformed, he says. "Even the drug companies are afraid to do that" for similar reasons, he adds. Additionally, cosmetic companies sometimes make conflicting claims for the same botanical extract.

Without side-by-side studies, dermatologists use experience and anecdotal evidence to place hydroquinone alternatives in the following categories, in roughly descending order of efficacy:

Prescription products

Solage (mequinol, tretinoin; Barrier Therapeutics) outperforms OTC alternatives and is a prescription alternative to hydroquinone, says Zoe Draelos, M.D., clinical associate professor of dermatology, Wake Forest University School of Medicine, Winston-Salem, N.C., and a Dermatology Times editorial adviser.

Conversely, retinoids work by inhibiting tyrosinase and causing exfoliation, says Leslie S. Baumann, M.D., professor of dermatology, University of Miami, Miami, Fla.

Dr. Werschler adds, "Some believe skin gets sallow with age because it loses its cutaneous vasculature," while cumulative sun damage also thickens the epidermis.

In contrast, he says, "Retin-A tends to plump the skin, but also makes it a little pinkish. Many older women love that," although patients with rosacea should avoid retinoids.

Other retinoids that act as skin-smoothing agents, such as topical tazarotene, also can help both texture and pigmentation, Dr. Werschler says. Alpha and beta hydroxy acids (AHAs and BHAs) assist with exfoliation, Dr. Baumann says.

Botanical agents