A low dose of antidepressant may be almost as effective as oestrogen at reducing the number of hot flashes menopausal women have to endure, according to a new study.
Oestrogen therapy is still the best way to avert the sudden feelings of overheating, sweating and occasionally palpitations – the most common symptom of menopause – that can strike women from once a day to once an hour, day and night.
The US Food and Drug Administration approved one antidepressant medication, the selective serotonin reuptake inhibitor (SSRI) paroxetine, brand name Brisdelle, for treating hot flashes in 2013. Brisdelle, marketed as Paxil when used as an antidepressant, was the first non-hormonal option approved by the FDA.
Antidepressants are often used off-label to treat hot flashes, Hadine Joffe of the department of Psychiatry at Brigham and Women’s Hospital in Boston told Reuters Health. But at high doses, hormones are more effective than antidepressants, she said.
Joffe led the new study, which compared venlafaxine, the generic form of the antidepressant Effexor, against a lower dose of oestrogen.
In the trial, 97 women took half a milligram of low-dose estradiol daily, 96 took 75 milligrams of venlafaxine per day and 140 women took a placebo. All the study participants were menopausal or post-menopausal with an average of eight hot flashes per day at the start.
Two months later, the estradiol group was having an average of 3.9 hot flashes per day and the venlafaxine group was having 4.4 hot flashes. The placebo group had decreased to 5.5 per day.
Women were most satisfied with the estradiol, and least satisfied with the placebo, according to results published in JAMA Internal Medicine. About half the women taking venlafaxine said they were satisfied with it.
The prevailing opinion is that oestrogen treatment is more effective than drugs like venlafaxine, Joffe said, but these results indicate that the difference is small, and perhaps not meaningful, at a lower dose.
“Part of it is that the oestrogen dose we used was the low dose, while the higher dose has gotten the most attention and is more effective than the lower dose,” she said.
In 2012, the North American Menopause Society recommended that hormone therapy be used at the lowest possible dose in light of the large, long-term Women’s Health Initiative study that found a connection between combination oestrogen/progestin therapy used by postmenopausal women and an increased risk of breast cancer, heart disease and stroke.
But even at a low dose, hormone therapy was still more effective than venlafaxine in the current study, James A. Simon said.
Simon is a professor of obstetrics and gynaecology at George Washington University in Washington, D.C. and was not involved in the new study.
“The Women’s Health Initiative, which painted hormone therapy or oestrogen therapy in a very very negative light, made hormones much more difficult for menopausal women to take even if they were highly symptomatic with hot flashes,” he told Reuters Health.
Antidepressants like venlafaxine also have side effects, he noted. In the new study, some women in the venlafaxine group experienced nausea, stomach upset, sleepiness or high blood pressure.
In 2011, the FDA did not approve the antidepressant desvenlafaxine for treating hot flashes, even though the drug was effective, because of safety concerns that included high blood pressure, he noted.
“One of the major side effects of all the antidepressant-like drugs are sexual, and sexual dysfunction is already a problem in the menopausal population,” Simon said. “Some of them cause massive weight gain as well.”
Case reports have indicated that serious withdrawal symptoms may start within hours of going off venlafaxine.
While hot flashes are a normal aspect of menopause, they can interfere with sleep and daily life for some women, and treating them can improve quality of life, Heidi D. Nelson of Oregon Health & Science University in Portland told Reuters Health.
There are a few other options that are neither antidepressants nor hormones, including gabapentin, which treats pain syndrome, and an older blood pressure medication, Joffe said, but those are not widely used.
For most women, hot flashes last for about four to five years, and taking hormone therapy for that short amount of time should be safe, Joffe said. But for some women, symptoms last longer. In that case it may be a good idea to use venlafaxine to help come off or delay going on hormone therapy, she said.
Weighing the risks and benefits of the two main treatment options comes down to your personal health concerns, Joffe said.
In general, oestrogen is less expensive, but costs vary by the type of formulation, Nelson said.
For some women, like those with breast cancer, hormone therapy is not an option.
If a woman tries hormone therapy and isn’t satisfied with the effects or is bothered by side effects, she can switch to venlafaxine, or vice versa, Joffe said.
“We’re in a strong position to say that we can hopefully individualise this,” she said.