Herbal Remedy Cool to Hot Flashes
Black cohosh doesn't work for breast cancer patients
FRIDAY, May 18, 2001 (HealthDayNews) -- A well-known herbal remedy for menopause doesn't work for breast cancer survivors, a new study shows.
Columbia University researchers found that breast cancer survivors who took black cohosh pills got only as much relief from hot flashes as those who took a placebo. However, they add, the traditional Native American remedy won't hurt you.
"I would feel comfortable if a woman said she took this stuff and it made her feel better," says Dr. Victor R. Grann, a co-investigator on the study, which appears in this week's issue of the Journal of Clinical Oncology. "I would have no problem with that, even though I know a placebo would have the same effect."
What really matters, Grann says, is that more scientific studies are done on all alternative remedies: "It's just very important to use the same scientific principles as we do for other medicines."
Black cohosh is a tall, perennial herb that grows mostly in the northeastern United States. Native Americans used to boil the root, then drink the brew, which was used for everything from women's problems to arthritis to snakebites. Europeans have used it for decades, and a precise pill form has been marketed under the name Remifemin in Germany for several years.
With this study, researchers looked at the menopausal symptoms of 85 breast cancer survivors and tested their responses to black cohosh. Half were given the herbal pill, the other half got placebo pills. They were all observed for two months, at which point both groups reported about 27 percent fewer hot flashes and similar decreases in excessive sweating.
Grann says the findings point to a placebo effect, where the patients improved mostly because they thought they were getting real medicine. The study did have its limitations: It was brief, and healthy women were not included. Grann says there is a similar study of healthy women now underway at the university.
"It was a hard group to treat," says Dr. Steven Bratman, the medical editor of the Natural Pharmacist Web site and an author of numerous books on alternative remedies. "But it is part of a growing pattern of studies that say black cohosh doesn't work. I would just have to say there's no evidence for it."
Bratman did note, however, that tamoxifen, a drug given after breast cancer surgery to block the estrogen that can spur the growth of cancer cells, causes sudden and artificial menopause.
"It's possible that tamoxifen blocks the effects of black cohosh, too," he says. "In natural menopause, there is no blocking going on, only a deficit of estrogen and progesterone."
But Grann says researchers did take the menopausal effects of tamoxifen into account. About 60 percent of the women in the study were on the drug, so they were divided evenly into two groups; one took black cohosh and one took a placebo. The results were still similar to the group not on tamoxifen, he notes.
Because some physicians recommend that breast cancer patients don't take black cohosh because of possible estrogen-like properties, Grann says his research team carefully analyzed the black cohosh pills they used to make sure they had no estrogenic activity and did not raise estrogen levels in the women studied.
Bratman points out that one recent study even found the herb didn't act like estrogen, so scientists aren't clear on how it works. Because the Columbia study was one of the first with a placebo control, he suggests another placebo study would be needed to truly determine the herb's effectiveness.
In the meantime, there are few alternative treatments for hot flashes, Bratman says. Some soy studies have shown promise, and natural progesterone creams seem to work, but there aren't many choices beyond that.
Grann adds that synthetic progesterone pills and antidepressants work only to some degree.
A stronger dosage of black cohosh might be more effective, he adds: "In fairness, it didn't work and it didn't do any harm. But we should do this kind of study."
What To Do
For more on all the treatments for breast cancer, visit the American Cancer Society.
For all the details on black cohosh, go here.
For more on breast cancer and soy, read these HealthScout stories.
Visit Veritas Medicine to learn about clinical trials for breast cancer.