If you have experienced hot flashes, you're already well aware that they are sudden sensations of intense body heat, often with heavy sweating and reddening of the head, neck, and chest or the entire body. At night, they commonly cause drenching "night sweats," making them a cause of sleep problems for perimenopausal and post-menopausal women.

During a typical hot flash, your skin temperature rises. Although you may feel very warm during a hot flash, because of the heat lost by your body's cooling mechanism (perspiration), your body temperature may actually drop. Some women feel chilly after a hot flash, and some women feel the chill without the flash.

The biochemical cause of hot flashes is not well understood. But they are linked to declining estrogen levels, and they do seem to be made worse by stress, heavy alcohol use, and cigarette smoking. Although menopausal hot flashes can be disruptive, frustrating, and at times embarrassing, they are medically harmless. They are not a sign of a medical problem, nor do they cause medical problems.

It is normal for hot flashes to:

• Happen in women of all ages when they are upset or embarrassed.
• Happen during the perimenopausal years before menopause, when estrogen levels fluctuate. They are most common, most frequent, and most intense during the 2 years following menopause (post-menopause), when estrogen declines.
• Be accompanied by mild to severe heart palpitations, anxiety, or irritability. In rare cases, panic attacks are triggered at the same time as hot flashes, usually in women who have a history of panic attacks.
• Be especially severe in women who become menopausal from chemotherapy, anti-estrogen treatment for breast cancer, or surgical removal of the ovaries.
• Subside within a couple of years after menopause. But some women do continue to have hot flashes for years after menopause. There is no reliable method for predicting whether, when, or how long you will have hot flashes.

Hot flashes are uncommon in various places around the world. More research is necessary before experts can identify specific factors about Canadian and American women's environment and lifestyle that make hot flashes a common problem.

Continue to Why?

Hot flashes are a normal part of perimenopause for most women. If yours are mild or infrequent, there is no need to treat them. But it's common to look for relief of moderate to severe or frequent hot flashes that disrupt your daily life and sleep.

You may not have to "treat" hot flashes to prevent them or get them under control. Making healthy lifestyle choices is your best and first choice for hot flashes and can make a big difference in how your body handles the transition to menopause. But if hot flashes are frequent and powerful, additional treatment may be needed to help you get enough sleep or lead a predictable daily life.

Continue to How?

You can manage hot flashes by making certain lifestyle choices. You can also take daily medicine. Some measures help prevent or reduce hot flashes, and others can make you more comfortable when you're having a hot flash. If you are looking for additional treatment measures, you have a few options to choose from.

Lifestyle choices for preventing or reducing hot flashes

Eat and drink well, and avoid smoking.

• Limit your intake of alcohol.
• Drink cold beverages rather than hot ones.
• Eat smaller, more frequent meals to avoid the heat generated by digesting large amounts of food.
• Eat plenty of low-fat, high-fibre foods.
• Do not smoke or use other forms of tobacco.

Stay cool.

• Keep your environment cool, or use a fan.
• Dress in layers, so you can remove clothes as needed.
• Wear natural fabrics, such as cotton and silk.
• Sleep with fewer blankets.

Reduce stress.

• Get regular physical exercise.
• Use relaxation techniques, such as breathing exercises, yoga, or biofeedback. Using a breathing-for-relaxation exercise called paced respiration may reduce hot flashes and emotional symptoms.

Medical treatment options for hot flashes

• Short-term, low-dose hormone replacement therapy (HRT) can reduce or stop hot flashes and other perimenopausal symptoms by raising your body's estrogen level. Use the lowest dose needed for the shortest possible time and have regular checkups. This is because HRT may increase the risk of blood clots, stroke, heart disease, breast cancer, ovarian cancer, and dementia in a small number of women.^{1, 2} And HRT users who are 10 or more years past menopause are also at higher risk for heart disease.³ If you have a history of cardiovascular disease or breast cancer, avoid using estrogen for hot-flash relief—other options are available.
• Estrogen-progestin birth control pills (before menopause) can reduce or stop hot flashes and other perimenopausal symptoms by evening out fluctuating hormones. Don't use estrogen for hot-flash relief if you are older than 35 and smoke; have diabetes, cardiovascular disease, or breast cancer; or have a family history of these conditions. Other options are available.
• Antidepressant medicine can reduce the number and severity of hot flashes by improving the brain's use of serotonin, which helps regulate body temperature.⁴ Side effects are possible. This type of medicine is a good choice if hot flashes, irritability, or mood swings are your only perimenopausal symptom.
• Clonidine may relieve hot flashes for some women. But studies have not shown that clonidine makes hot flashes less severe or less frequent.⁵ This type of medicine is a good choice if hot flashes are your only perimenopausal symptom, especially if you have high blood pressure.
• Gabapentin, an antiseizure medicine, may lower the number of hot flashes each day and the intensity of hot flashes.^{6, 7}
• Black cohosh may reduce or prevent hot flashes, depression, and anxiety. As with HRT, have regular checkups when taking black cohosh. Health Canada advises that you talk to your doctor before using black cohosh if you have liver problems or if you develop symptoms of liver problems after using black cohosh. Symptoms of liver damage can include being more tired than usual, feeling weak, loss of appetite, and yellowing of the skin.⁸
• Some women eat and drink a lot of soy to even out hot flashes and other perimenopausal symptoms. So far, studies have used many different soy sources and different measures of success, which are hard for experts to compare. Soy isoflavone (rather than soy protein) studies have shown the most promise for hot flash treatment.⁹

Continue to Where?

If you are having problems with hot flashes, discuss them with your doctor at your next regularly scheduled appointment. If your hot flashes are so severe that they are disrupting your sleep or affecting another area of your life, call your doctor to discuss your hot flashes.

If you would like more information about menopausal changes, see the topic Menopause and Perimenopause.

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