Popular alternative therapy for psoriasis performs no better than placebo

Anecdotal evidence touting the healing power of the Indian spice turmeric for psoriasis received a setback in a prospective study published this month by a leading dermatology journal stating that the low response rate of patients who ingested the active ingredient of the exotic spice was probably a result of the placebo effect.

Researchers at the University of Pennsylvania School of Medicine found that despite strong scientific evidence in the laboratory demonstrating the ability of curcumin (the active ingredient in the spice turmeric) to inhibit a critical pathway of psoriasis, the positive response in patients was so low that scientists suggest the placebo effect or the disease’s natural remission might be the reason. The study was published in the Journal of the American Academy of Dermatology.

“Alternative and complementary websites and newspapers publish anecdotal reports that the Indian spice has been successfully used to treat psoriasis,” says Joel M. Gelfand, MD, MSCE, of The University of Pennsylvania School of Medicine. “However, spontaneous improvements in psoriasis are common, and based on our study, until larger, placebo-controlled trials are conducted, oral curcumin should not be recommended for the treatment of psoriasis given lack of proven efficacy.”

But the researchers do not discount entirely the potential of curmumin as a treatment for psoriasis.

They recognize that current traditional pharmacologic approaches in the treatment of psoriasis are costly and have their limitations, including the risk of infections and possibly malignancies with long-term use resulting in many patients with the disease unable to achieve effective long-term control. Turning to complementary and alternative therapies is understandable, they say. In fact, of the estimated 7 million diagnosed with psoriasis, it is estimated that 51% use complementary and alternative medicine therapies to treat their skin.

The excellent responses that were observed in two of the 12 patients in the study suggest that curcumin may have promise for a small subset of patients with psoriasis. Large, placebo-controlled trials are necessary to definitively prove or disprove oral curcumin as a potential therapeutic agent for psoriasis. “What is needed is scientific data to assess the safety and efficacy of these treatments so that we may more rationally inform patients of their treatment options,” says Gelfand.