By Frederik Joelving
NEW YORK (Reuters Health) - Breast cancer survivors who struggle with hot flashes may find respite in an antidepressant, according to a new study that suggests the medication should be the go-to drug when the overheating is severe.
Most women get hot flashes when their estrogen levels start to plummet in menopause, but the symptoms may be especially taxing for breast cancer patients who've received chemotherapy or estrogen-blocking drugs.
However, doctors are reluctant to prescribe hormone replacement therapy -- the standard drug therapy -- to such women, because it might fuel tumor growth.
Instead, they've begun using antidepressants and gabapentin (Neurontin), an epilepsy medicine also used to treat certain types of pain.
The new study, published in the Journal of Clinical Oncology, shows for the first time that although gabapentin was just as effective and safe as the antidepressant venlafaxine (Effexor), most women chose the latter.
"For some people, venlafaxine works better than gabapentin and for others, gabapentin works better," said Dr. Charles Loprinzi, a breast cancer researcher at the Mayo Clinic in Rochester, Minnesota, who worked on the new study.
"The patients in the end preferred venlafaxine by two-thirds to one-third," he said.
The researchers studied a group of 66 women with a minimum of two "bothersome" hot flashes per day. The women were randomly assigned to take first one drug for a month, then the other, and jotted down the severity and frequency of their hot flashes.
Both drugs, which can be purchased in the U.S. for about $20 per month, cut severity by two-thirds. Whether a woman favored one drug or the other depended largely on which had helped her symptoms more.
Some women also reported side effects, such as nausea, constipation, appetite loss and orgasm difficulty on venlafaxine, and negative mood changes, increased appetite and dizziness on gabapentin.
"If a person wants to have their hot flashes go away the best way to do that is to use a hormone," said Loprinzi. "If it's preferred to do it in a non-hormone manner, then it makes sense to use venlafaxine or another new antidepressant or gabapentin."
For many women, menopausal hot flashes are manageable and gradually subside within a couple years. For others, they are longer lasting and more severe.
"I find that unless women are really bothered, they don't want to take a drug," Dr. Patricia A. Ganz, who was not involved in the research, said in an e-mail to Reuters Health.
"However, those that are can try one of several different effective drugs. This trial suggests that venlafaxine should be tried first, since it was effective and preferred," added Ganz, a professor at the University of California, Los Angeles, Schools of Medicine & Public Health.
She added that women without a history of cancer could also take the drugs.
"I have given them to women at high risk for breast cancer who are on (the estrogen-blocking drug) tamoxifen," she said.
The study was funded by the Ontario chapter of the Canadian Breast Cancer Foundation, but some of the authors have received funding from companies that make antidepressants.
Drug-free treatments with fewer side effects also exist, although there is more controversy about their use.
Earlier this year, for instance, Dr. Eleanor M. Walker of Henry Ford Hospital in Detroit found that acupuncture was just as helpful as venlafaxine in women treated with tamoxifen.
"I generally recommend acupuncture if the patient can afford it or if their insurance partially covers it," Walker said in an e-mail. "I think the literature is showing that acupuncture is equivalent to drug therapy without the side effects."
"I think women should discuss their options with their doctors to determine what treatment options would be best for them," she added.
SOURCE: http://link.reuters.com/byd27m Journal of Clinical Oncology, online November 8, 2010.