Hot flush
Encyclopedia
Hot flashes are a symptom of the changing hormone
levels that are considered to be characteristic of menopause
.
Hot flashes, a common symptom of menopause
and perimenopause, are typically experienced as a feeling of intense heat with sweating and rapid heartbeat
, and may typically last from two to thirty minutes for each occurrence. The sensation of heat usually begins in the face or chest, although it may appear elsewhere such as the back of the neck, and it can spread throughout the whole body. Some women pass out if the effects are strong enough. In addition to being an internal sensation, the surface of the skin, especially on the face, becomes hot to the touch. This is the origin of the alternative term "hot flush," since the sensation of heat is often accompanied by visible reddening of the face. Excessive flushing can lead to rosacea
.
The hot-flash event may be repeated a few times each week or constantly throughout the day, with the frequency reducing over time. Hot flashes may begin to appear several years before menopause starts and last for years afterwards. Some women undergoing menopause never have hot flashes. Others have mild or infrequent flashes. The worst sufferers experience dozens of hot flashes each day. In addition, hot flashes are often more frequent and more intense during hot weather or in an overheated room, the surrounding heat apparently making the hot flashes themselves both more probable and more severe.
Severe hot flashes can make it difficult to get a full night's sleep (often characterized as insomnia
), which in turn can affect mood, impair concentration, and cause other physical problems. When hot flashes occur at night, they are called "night sweats." As estrogen
is typically lowest at night, some women get night sweats without having any hot flashes during the daytime.
Slow "ember" flashes appear almost as quickly but are less intense and last for around half an hour. Women who experience them may undergo them year-round, rather than primarily in the summer, and ember flashes may linger for years after the more intense hot flashes have passed.
or expecting to menstruate soon (the premenstrual period typically lasts one week) may encounter hot and/or cold flashes. These episodes do not usually last long, with feelings of cold and heat alternating over the course of as short as a minute. Hot and cold flashes for younger women tend to occur only during times of menstruation or pre-menstruation (when oestrogen is typically lowest). If they occur at other times in a young woman's menstrual cycle, then it might be a symptom of a problem with her pituitary gland
; seeing a doctor is highly recommended. In younger women who are surgically menopausal, hot flashes are generally more intense than in older women, and they may last until natural age at menopause.
may relieve many of the symptoms of menopause. However, HRT may increase the risk of breast cancer, stroke, and dementia and has other potentially serious short-term and long-term risks
The U.S. FDA and women's health advocates recommend that women who experience troublesome hot flashes try alternatives to hormonal therapies as the first line of treatment. If a woman chooses hormones, they suggest she take the lowest dose that alleviates her symptoms for as short a time as possible.
, a drug used in the treatment of some types of breast cancer
and which can cause hot flashes as a side effect, RAD1901, Raloxifene
and the soy-derived Femarelle (DT56a)
are examples of SERMs. Menerba, a botanically derived selective estrogen receptor beta agonist currently under development, works like a SERM, but only activates on the estrogen receptor beta.
and daidzein
, and are also known as phytoestrogens
. The half life of these molecules is about eight hours, which might explain why some studies have not consistently shown effectiveness of soy products for menopausal symptoms. Although red clover (Trifolium pratense) contains isoflavones similar to soy, the effectiveness of this herb for menopausal symptoms at relatively low concentrations points to a different mechanism of action.
from sources such as soy, red clover, ginseng, and yam may relieve hot flashes.
or testicular cancer
can also have hot flashes, especially those who are undergoing hormone therapy with antiandrogens, also known as androgen antagonists, which reduce testosterone to castrate levels. There are also other ailments and even dietary changes which can cause it Men who are castrated can also get hot flashes.
Hormone
A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...
levels that are considered to be characteristic of menopause
Menopause
Menopause is a term used to describe the permanent cessation of the primary functions of the human ovaries: the ripening and release of ova and the release of hormones that cause both the creation of the uterine lining and the subsequent shedding of the uterine lining...
.
Presentation
Hot flashes, a common symptom of menopause
Menopause
Menopause is a term used to describe the permanent cessation of the primary functions of the human ovaries: the ripening and release of ova and the release of hormones that cause both the creation of the uterine lining and the subsequent shedding of the uterine lining...
and perimenopause, are typically experienced as a feeling of intense heat with sweating and rapid heartbeat
Heart rate
Heart rate is the number of heartbeats per unit of time, typically expressed as beats per minute . Heart rate can vary as the body's need to absorb oxygen and excrete carbon dioxide changes, such as during exercise or sleep....
, and may typically last from two to thirty minutes for each occurrence. The sensation of heat usually begins in the face or chest, although it may appear elsewhere such as the back of the neck, and it can spread throughout the whole body. Some women pass out if the effects are strong enough. In addition to being an internal sensation, the surface of the skin, especially on the face, becomes hot to the touch. This is the origin of the alternative term "hot flush," since the sensation of heat is often accompanied by visible reddening of the face. Excessive flushing can lead to rosacea
Rosacea
Rosacea is a chronic condition characterized by facial erythema . Pimples are sometimes included as part of the definition. Unless it affects the eyes, it is typically a harmless cosmetic condition...
.
The hot-flash event may be repeated a few times each week or constantly throughout the day, with the frequency reducing over time. Hot flashes may begin to appear several years before menopause starts and last for years afterwards. Some women undergoing menopause never have hot flashes. Others have mild or infrequent flashes. The worst sufferers experience dozens of hot flashes each day. In addition, hot flashes are often more frequent and more intense during hot weather or in an overheated room, the surrounding heat apparently making the hot flashes themselves both more probable and more severe.
Severe hot flashes can make it difficult to get a full night's sleep (often characterized as insomnia
Insomnia
Insomnia is most often defined by an individual's report of sleeping difficulties. While the term is sometimes used in sleep literature to describe a disorder demonstrated by polysomnographic evidence of disturbed sleep, insomnia is often defined as a positive response to either of two questions:...
), which in turn can affect mood, impair concentration, and cause other physical problems. When hot flashes occur at night, they are called "night sweats." As estrogen
Estrogen
Estrogens , oestrogens , or œstrogens, are a group of compounds named for their importance in the estrous cycle of humans and other animals. They are the primary female sex hormones. Natural estrogens are steroid hormones, while some synthetic ones are non-steroidal...
is typically lowest at night, some women get night sweats without having any hot flashes during the daytime.
Types of hot flashes
Some menopausal women may experience both standard hot flashes and a second type sometimes referred to as "slow hot flashes" or "ember flashes." The standard hot flash comes on rapidly, sometimes reaching maximum intensity in as little as a minute. It lasts at full intensity for only a few minutes before gradually fading.Slow "ember" flashes appear almost as quickly but are less intense and last for around half an hour. Women who experience them may undergo them year-round, rather than primarily in the summer, and ember flashes may linger for years after the more intense hot flashes have passed.
In younger women
Younger women who are menstruatingMenstruation
Menstruation is the shedding of the uterine lining . It occurs on a regular basis in sexually reproductive-age females of certain mammal species. This article focuses on human menstruation.-Overview:...
or expecting to menstruate soon (the premenstrual period typically lasts one week) may encounter hot and/or cold flashes. These episodes do not usually last long, with feelings of cold and heat alternating over the course of as short as a minute. Hot and cold flashes for younger women tend to occur only during times of menstruation or pre-menstruation (when oestrogen is typically lowest). If they occur at other times in a young woman's menstrual cycle, then it might be a symptom of a problem with her pituitary gland
Pituitary gland
In vertebrate anatomy the pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and weighing 0.5 g , in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain, and rests in a small, bony cavity covered by a dural fold...
; seeing a doctor is highly recommended. In younger women who are surgically menopausal, hot flashes are generally more intense than in older women, and they may last until natural age at menopause.
Hormone replacement therapy
Hormone replacement therapyHormone replacement therapy (menopause)
Hormone replacement therapy is a system of medical treatment for surgically menopausal, perimenopausal and to a lesser extent postmenopausal women...
may relieve many of the symptoms of menopause. However, HRT may increase the risk of breast cancer, stroke, and dementia and has other potentially serious short-term and long-term risks
The U.S. FDA and women's health advocates recommend that women who experience troublesome hot flashes try alternatives to hormonal therapies as the first line of treatment. If a woman chooses hormones, they suggest she take the lowest dose that alleviates her symptoms for as short a time as possible.
Selective estrogen receptor modulators
SERMs are a category of drugs that act selectively as agonists or antagonists on the estrogen receptors throughout the body. TamoxifenTamoxifen
Tamoxifen is an antagonist of the estrogen receptor in breast tissue via its active metabolite, hydroxytamoxifen. In other tissues such as the endometrium, it behaves as an agonist, hence tamoxifen may be characterized as a mixed agonist/antagonist...
, a drug used in the treatment of some types of breast cancer
Breast cancer
Breast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas...
and which can cause hot flashes as a side effect, RAD1901, Raloxifene
Raloxifene
Raloxifene is an oral selective estrogen receptor modulator that has estrogenic actions on bone and anti-estrogenic actions on the uterus and breast...
and the soy-derived Femarelle (DT56a)
Femarelle (DT56a)
Femarelle is as a selective estrogen receptor modulator for the treatment of menopause and bone health. DT56a is a standardized compound derived from soybean.-Mode of Action:...
are examples of SERMs. Menerba, a botanically derived selective estrogen receptor beta agonist currently under development, works like a SERM, but only activates on the estrogen receptor beta.
Selective serotonin reuptake inhibitors
SSRIs are a class of antidepressants most commonly used in the treatment of depression, and some personality disorders. They have been found as efficient in alleviating hot flashes.Isoflavones
Isoflavones are commonly found in legumes such as soy and red clover. The two soy isoflavones implicated in relieving menopausal symptoms are genisteinGenistein
Genistein is one of several known isoflavones. Isoflavones, such as genistein and daidzein, are found in a number of plants including lupin, fava beans, soybeans, kudzu, and psoralea being the primary food source, also in the medicinal plant, Flemingia vestita and coffee Besides functioning as...
and daidzein
Daidzein
Daidzein belongs to the group of isoflavones. Daidzein and other isoflavone compounds, such as genistein, are present in a number of plants and herbs like the Thai Kwao Krua or Pueraria mirifica, Kudzu or Pueraria lobata, and in food sources such as soybeans and soy products like tofu and textured...
, and are also known as phytoestrogens
Phytoestrogens
Phytoestrogens are plant-derived xenoestrogens functioning as the primary female sex hormone not generated within the endocrine system but consumed by eating phytoestrogonic plants...
. The half life of these molecules is about eight hours, which might explain why some studies have not consistently shown effectiveness of soy products for menopausal symptoms. Although red clover (Trifolium pratense) contains isoflavones similar to soy, the effectiveness of this herb for menopausal symptoms at relatively low concentrations points to a different mechanism of action.
Other phytoestrogens
It is believed that dietary changes that include a higher consumption of phytoestrogensPhytoestrogens
Phytoestrogens are plant-derived xenoestrogens functioning as the primary female sex hormone not generated within the endocrine system but consumed by eating phytoestrogonic plants...
from sources such as soy, red clover, ginseng, and yam may relieve hot flashes.
- GinsengGinsengGinseng is any one of eleven species of slow-growing perennial plants with fleshy roots, belonging to the genus Panax of the family Araliaceae....
- Very few studies exist on the effect of ginseng for relief of menopausal symptoms; however, hundreds of years of anecdotal evidence exists using ginseng as part of tonics made by Chinese herbalists. In a large double-blinded randomized controlled trial, reduction in hot flashes was not statistically significant but showed a strong trend towards improvement.
- Flaxseed - There have also been several clinical trials using flaxseed. Flaxseed is the richest source of lignanLignanThe lignans are a group of chemical compounds found in plants. Lignans are one of the major classes of phytoestrogens, which are estrogen-like chemicals and also act as antioxidants. The other classes of phytoestrogens are the isoflavones and coumestans...
s, which is one of three major classes of phytoestrogen. Lignans are thought to have estrogen agonist and antagonist effects as well as antioxidant properties. Flaxseed and its lignans may have potent anti-estrogenic effects on estrogen receptor positive breast cancer and may have benefits in breast cancer prevention efforts. One recent study done in France, looked at four types of lignans, including that found in flaxseed (Secoisolariciresinol) in a prospective cohort study to see if intake predicted breast cancer incidence. The authors report lowered risk of breast cancer among over 58,000 postmenopausal women who had the third highest quartile of lignan intake. There have been a few small pilot studies that have tested the effect of flaxseed on hot flashes. Currently there is a large study sponsored by the National Cancer Institute that is enrolling patients http://clinicaltrials.gov/ct2/show/NCT00956813. The rationale for the study is that estrogen can relieve the symptoms of menopause, but can also cause the growth of breast cancer cells. Flaxseed may reduce the number of hot flashes and improve mood and quality of life in postmenopausal women not receiving estrogen therapy.
Lifestyle changes
Lifestyle changes may help alleviate hot flashes. These include avoiding caffeine, hot drinks, chocolate, spicy or hot foods and alcohol.In men
Hot flashes in men could have various causes. One is a possible sign of low testosterone or embarrassment. Another is andropause, or "male menopause." Men with prostate cancerProstate cancer
Prostate cancer is a form of cancer that develops in the prostate, a gland in the male reproductive system. Most prostate cancers are slow growing; however, there are cases of aggressive prostate cancers. The cancer cells may metastasize from the prostate to other parts of the body, particularly...
or testicular cancer
Testicular cancer
Testicular cancer is cancer that develops in the testicles, a part of the male reproductive system.In the United States, between 7,500 and 8,000 diagnoses of testicular cancer are made each year. In the UK, approximately 2,000 men are diagnosed each year. Over his lifetime, a man's risk of...
can also have hot flashes, especially those who are undergoing hormone therapy with antiandrogens, also known as androgen antagonists, which reduce testosterone to castrate levels. There are also other ailments and even dietary changes which can cause it Men who are castrated can also get hot flashes.
Regional variance
It has been speculated that hot flashes are considerably less common among Asian women, possibly owing to their soy rich diets.See also
- European Menopause and Andropause SocietyEuropean Menopause and Andropause SocietyThe European Menopause and Andropause Society is a medical association focused on the study and treatment of the climacteric in men and women...
- Hormone replacement therapyHormone replacement therapy (menopause)Hormone replacement therapy is a system of medical treatment for surgically menopausal, perimenopausal and to a lesser extent postmenopausal women...
- Menopausal Research and Info ServiceMenopausal Research and Info ServiceThe Menopausal Research & Info Service is a British medical research charity dedicated to the research into the menopause.-External links:* http://www.webhealth.co.uk/Self_Help_and_Support_Groups_R/The_Menopausal_Helpline_Limite/the_menopausal_helpline_limite.html...
- North American Menopause SocietyNorth American Menopause SocietyThe North American Menopause Society , founded in 1989, is a nonprofit multidisciplinary organization with the mission of promoting the health and quality of life of women during midlife and beyond through an understanding of menopause and healthy aging. Based in Cleveland, Ohio, NAMS has over...
, also known as NAMS