Menopause Centre of Australia

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: William C. Shiel, Jr., MD, FACP, FACR

• Introduction to menopause and hot flashes
• What are hot flashes?
• How are hot flashed usually treated?
• Which alternative prescription medications are effective in treating hot flash symptoms of menopause?
• Why are some doctors reluctant to recommend nonprescription therapies for menopause symptoms?
• What alternative treatments for menopause have been scientifically studied?
• Alternatives for Treating Hot Flashes At A Glance
• Explore More Menopause Articles

Introduction to menopause and hot flashes

Hot flashes are experienced by many women, but not all women undergoing menopause experience hot flashes. A hot flash is a feeling of warmth that spreads over the body, but is often most strongly felt in the head and neck regions. Hot flashes may be accompanied by perspiration or flushing. Hot flashes usually last from 30 seconds to several minutes. Although the exact cause of hot flashes is not fully understood, hot flashes are thought to be due to a combination of hormonal and biochemical fluctuations brought on by declining estrogen levels.

Hot flashes occur in up to 40% of regularly menstruating women in their forties, so they often begin before the menstrual irregularities characteristic of menopause even begin. About 80% of women will be finished having hot flashes after five years. Sometimes (in about 10% of women), hot flashes can last as long as 10 years.

Sometimes hot flashes are accompanied by night sweats (episodes of drenching sweats at nighttime). This may lead to awakening and difficulty falling asleep again, resulting in unrefreshing sleep and daytime tiredness.

How are hot flashes usually treated?

Traditionally, hot flashes have been treated with either oral (by mouth) or transdermal (patch) forms of estrogen. Hormone therapy (HT), also referred to as hormone replacement therapy (HRT) or postmenopausal hormone therapy (PHT), consists of estrogens or a combination of estrogens and progesterone (progestin). Both oral and transdermal estrogen are available either as estrogen alone or estrogen combined with progesterone (see the Hormone Replacement Therapy article). All available prescription estrogen replacement medications, whether oral or transdermal, are effective in reducing the frequency of hot flashes and their severity. Generally, these medications decrease the frequency of hot flashes by about 80 to 90%.

However, long-term studies (the NIH-sponsored Women’s Health Initiative, or WHI) of women receiving combined hormone therapy with both estrogen and progesterone were halted when it was discovered that these women had an increased risk for heart attack, stroke, and breast cancer when compared with women who did not receive HT. Later studies of women taking estrogen therapy alone showed that estrogen was associated with an increased risk for stroke, but not for heart attack or breast cancer. Estrogen therapy alone, however, is associated with an increased risk of developing endometrial cancer (cancer of the lining of the uterus) in postmenopausal women who have not had their uterus surgically removed.

The decision in regard to starting or continuing hormone therapy, therefore, is a very individual decision in which the patient and doctor must take into account the inherent risks and benefits of the treatment along with each woman's own medical history. It is currently recommended that if hormone therapy is used, it should be used at the smallest effective dose for the shortest possible time.

Which alternative prescription medications are effective in treating hot flash symptoms of menopause?

A few prescription medications, in addition to estrogen, can provide relief for hot flashes. While none of these drugs is as effective as estrogen, studies show that non-estrogen drugs may have up to 70% of the effectiveness of estrogen therapy when treating hot flashes.

1. Selective serotonin reuptake inhibitors (SSRI's): This class of medication is used to treat depression and anxiety. In clinical studies, however, low doses of SSRI's have been shown to be effective in decreasing menopausal hot flashes. The SSRI that has been tested most extensively is venlafaxine (Effexor), although there is also evidence showing that paroxetine (Paxil, Paxil CR) and fluoxetine (Prozac) can be effective in controlling hot flashes.
2. Clonidine: Clonidine (Catapres) acts in the brain to decrease blood pressure. It has a long history of being used for blood pressure control, but it has potentially annoying side effects, such as dry mouth, constipation, drowsiness, or difficulty sleeping. Clonidine effectively relieves hot flashes in some women but is completely ineffective in others. Clonidine is available in pill or patch form.
3. Megestrol acetate (Megace): This medication is a type of progesterone, a female hormone. It can be effective in relieving hot flashes, but can only be taken over the short term (for several months). Serious effects can occur if the medication is abruptly discontinued, and megestrol is not usually recommended as a first-line drug to treat hot flashes. Megestrol use can also lead to weight gain.
4. Studies of another form of progesterone, medroxyprogesterone acetate (Depo-Provera), which is administered by injection, have also shown that this medication may be useful in treating hot flashes. This drug can be used long-term but may have side effects that include weight gain and bone loss.
5. Gabapentin: Gabapentin (Neurontin) is a drug that is primarily used for the treatment of seizures that appears to be moderately effective in treating hot flashes. The drug is well tolerated by most women, but often causes drowsiness.

Why are some doctors reluctant to recommend nonprescription therapies for menopause symptoms?

Nonprescription products are not controlled by the FDA because they are considered food supplements by law. Because they are not regulated like prescription medications, their ingredients and potency vary from manufacturer to manufacturer, and even from bottle to bottle from the same manufacturer. Also, careful testing and proof of safety is not required as it is with prescription medications. (The only way the FDA can recall a nonprescription product is by proving that it is dangerous.) Furthermore, there are so many nonprescription products available that a doctor cannot possibly know exactly what is in each preparation. Moreover, not one of these products has been scientifically proven to be safe.

So, how well have the nonprescription alternatives to hormone therapy been tested? Not one study has adhered to all of the stringent requirements that are necessary for approval of prescription medicines.

1. Specifically, sugar pills (placebos) have not been included in many studies of nonprescription alternative medications. Therefore, it is not possible to know if the product worked at all, since any effects seen with the product might have been seen with a placebo.
2. Many studies evaluated women who were taking products without supervision. Obviously, these women were aware that they were taking something to improve their symptoms. Thus, the element of objectivity was eliminated, and bias was introduced.
3. Most available studies have been carried out for only a few months. Physicians do not want to recommend a product that hasn't been proven safe over the long-term.
4. Lastly, each study seems to have a different way of judging whether the medication helps. Some analyze hot flashes alone, while others evaluate a group of symptoms without specifically segregating out hot flashes. Other studies examine multiple but individual symptoms. Even the studies that evaluate hot flashes may record different factors; the number of hot flashes per day, the severity of the hot flashes, or the duration of the hot flashes, etc.

It is confusing, even for doctors who are experts in the field, to evaluate these studies and properly counsel women. For more, please read "Evaluating Treatment Products, A Doctors' Perspective

What alternative treatments for menopause have been scientifically studied?

The alternative treatments for menopause that have been studied in well-designed trials include phytoestrogens (plant estrogens, isoflavones), black cohosh, and vitamin E.

Phytoestrogens

Isoflavones are chemical compounds found in soy and other plants (such as chick peas and lentils) that are phytoestrogens, or plant-derived estrogens. They have a chemical structure that is similar to the estrogens naturally produced by the body, but their effectiveness as an estrogen has been estimated to be much lower than true estrogens.

Some studies have shown that these compounds may help relieve hot flashes and other symptoms of menopause. In particular, women who have had breast cancer and do not want to take hormone therapy (HT) with estrogen sometimes use soy products for relief of menopausal symptoms. However, some phytoestrogens can actually have anti-estrogenic properties in certain situations, and the overall risks of these preparations have not yet been determined. For example, researchers have shown that long-term use of phytoestrogens in postmenopausal women led to an increase in endometrial hyperplasia (overgrowth of the tissues lining the uterus) which can be a precursor to cancer.

There is also a perception among many women that plant estrogens are "natural" and therefore safer than HT, but this has never been proven scientifically. Further research is needed to fully characterize the safety and potential risks of phytoestrogens.

Black Cohosh

Black cohosh is an herbal preparation that has been popular in Europe for the relief of hot flashes. This herb is becoming more and more popular in the U.S., and the North American Menopause Society does support the short-term use of black cohosh for treating menopausal symptoms, for a period of up to six months, because of its relatively low incidence of side effects when used over the short term. Some studies have shown that black cohosh can reduce hot flashes, but most of the studies have not been considered to be rigorous enough in their design to firmly prove any benefit. There have also not been scientific studies done to establish the long-term benefits and safety of this product. Research is ongoing to further determine the effectiveness and safety of black cohosh.

Vitamin E

Some women report that vitamin E supplements can provide relief from mild hot flashes, but scientific studies are lacking to prove the effectiveness of vitamin E in relieving hot flashes. Taking a dosage greater than 400 international units (IU) of Vitamin E may not be safe, since some studies have suggested that greater dosages may be associated with cardiovascular disease risk.

Other alternative therapies

There are many supplements and substances that have been advertised as "natural" treatments for symptoms of menopause, including licorice, evening primrose oil, dong quai, chasteberry, and wild yam. Scientific studies to prove the safety and effectiveness of these products have not been performed

Alternatives for Treating Hot Flashes At A Glance

• Each woman experiences menopause differently. Treatment, if necessary, is directed toward the particular symptoms that are present.

• Hot flashes are experienced by many but not all women undergoing menopause. A hot flash is a feeling of warmth, sometimes associated with flushing, that spreads over the body and may be accompanied by perspiration.

• Often it is not simple to determine if a given symptom is due to menopause. A physician should be consulted regarding symptoms that are new or of unknown cause.

• While "natural" menopause remedies may be effective, there is a lack of research on the safety and effectiveness of many of these remedies. Side effects of prescription remedies are generally better understood than those of over-the-counter medications and "natural" remedies.

• The most effective treatment for hot flashes is estrogen. However, the risks and benefits of this therapy must be carefully considered by a woman and her physician.

• Other prescription medications, including SSRIs, may also be effective in relieving hot flashes.

• Non-prescription products that have been used to treat hot flashes include phytoestrogens (plant estrogens), black cohosh, and vitamin E. However, studies that attest to their effectiveness and long-term safety are lacking.

Previous contributing medical author: Carolyn J. Crandall, M.D., M.S., F.A.C.P.