Hot flash
Hot flash | |
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Other names | Hot flushes |
Gynecology |
Hot flashes (formally known as hot flushes) are a form of flushing, often caused by the changing hormone levels that are characteristic of menopause. They are typically experienced as a feeling of intense heat with sweating and rapid heartbeat, and may typically last from two to 30 minutes for each occurrence.
Signs and symptoms
Hot flashes, a common symptom of
The hot-flash event may be repeated a few times each week or every few minutes throughout the day. Hot flashes may begin to appear several years before menopause starts and last for years afterwards. Some people undergoing menopause never have hot flashes. Others have mild or infrequent flashes. Those most affected 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 likely to occur, 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 people get night sweats without having any hot flashes during the daytime.[2]
Young females
If hot flashes occur at other times in a young female's menstrual cycle, then it might be a symptom of a problem with the pituitary gland; seeing a doctor is highly recommended. In younger females who are surgically menopausal, hot flashes are generally more intense than in older females, and they may last until natural age at menopause.[3]
Males
Hot flashes in males could have various causes. It can be a sign of low testosterone.
Types
Some menopausal females 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. Females 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.
Mechanism
Research on hot flashes is mostly focused on treatment options. The exact cause and pathogenesis, or causes, of vasomotor symptoms (VMS)—the clinical name for hot flashes—has not yet been fully studied.[11][12]
Hot flashes are associated with declining levels of estrogen (estrogen withdrawal) and other hormonal changes.[13] It does not appear that low levels of estrogen are the sole cause of hot flashes, as women who experience hot flashes have around the same plasma estrogen levels as women who do not have them, and prepubertal girls do not have hot flashes despite low estrogen levels.[13]
There are indications that hot flashes may be due to a change in the hypothalamus's control of temperature regulation.[14]
Treatment
Hormone replacement therapy
Women who experience troublesome hot flashes are advised by some to 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.[23] The US Endocrine Society concluded that women taking hormone replacement therapy for 5 years or more experienced overall benefits in their symptoms including relief of hot flashes and symptoms of urogenital atrophy and prevention of fractures and diabetes.[24]
When estrogen as estradiol is used transdermally as a patch, gel, or pessary with micronized progesterone this may avoid the serious side effects associated with oral estradiol HRT since this avoids first pass metabolism (Phase I drug metabolism).[25] Women taking bioidentical estrogen, orally or transdermally, who have a uterus must still take a progestin or micronized progesterone to lower the risk of endometrial cancer. A French study of 80,391 postmenopausal women followed for several years concluded that estrogen in combination with micronized progesterone is not associated with an increased risk of breast cancer.[26] The natural, plant-derived progesterone creams sold over the counter contain too little progesterone to be effective. Wild yam (Dioscorea villosa) extract creams are not effective since the natural progesterone present in the extract is not bioavailable.[27]
Selective serotonin reuptake inhibitors
Clonidine
Clonidine is a blood pressure-lowering medication that can be used to relieve menopausal hot flashes when hormone replacement therapy is not needed or not desired. For hot flashes, clonidine works by helping reduce the response of the blood vessels to stimuli that cause them to narrow and widen.[30] While not all women respond to clonidine as a hot flash medication, it can reduce hot flashes by 40% in some peri-menopausal women.[31]
Isoflavones
Other phytoestrogens
It is believed [
- Ginseng: Very few studies exist on the effect of ginseng for relief of menopausal symptoms. In a large double-blinded randomized controlled trial, reduction in hot flashes was not statistically significant but showed a strong trend towards improvement.[33] Lack of statistical significance suggests future research, but does not meet the scientific bar for ginseng to be deemed effective.
- Flaxseed: There have also been several clinical trials using flaxseed. Flaxseed is the richest source of lignans, which is one of three major classes of phytoestrogen.[34] 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.[35][36] 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.[36] 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 ongoing, but not accepting any new participants.[37]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.
Acupuncture
Acupuncture has been suggested to reduce incidence of hot flashes in women with breast cancer and men with prostate cancer, but the quality of evidence is low.[38][39]
Epidemiology
It has been speculated that hot flashes are less common among
Menopausal women who have more hot flashes have a higher risk of hypertension and cardiovascular disease.[42]
See also
- Hypoglycemia (low blood sugar) can cause similar symptoms
- Hyperthermia
References
- ^ "Hot Flashes - Symptoms and causes - Mayo Clinic". www.mayoclinic.org. Retrieved 31 March 2021.
- ^ University of Glasgow (24 October 2007). "Doctors seek the key to understanding hot flushes". University News (Archive of news). University of Glasgow. Retrieved 19 April 2013.
- ^ "Menopause". About.com. n.d. Archived from the original on 9 March 2011. Retrieved 19 April 2013.
- ^ Bunyavanich S (6 June 2007). "Low Testosterone Could Kill You". ABC News. ABC News Internet Ventures. Retrieved 20 April 2013.
- ^ "Hot Flashes in Men: An Update". Harvard Medical School. March 2014. Retrieved 5 May 2020.
- PMID 29094914.
- ^ "What to Expect During Therapy". Lupron Depot. Abbott Laboratories. Retrieved 20 April 2013.
- ^ "Hot Flashes in Men -- Mayo Clinic Researchers Describe A Treatment". ScienceDaily. Science Daily LLC. 19 October 2004. Retrieved 20 April 2013.
- S2CID 20123822.
- ^ Anitei S (16 April 2007). "Men Can Experience Hot Flashes, Just Like Women in Menopause". Softpedia. Retrieved 20 April 2013.
- ISSN 2161-3303.
- PMID 12440557.
- ^ PMID 24012626.
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- PMID 38138197.
- PMID 22028996.
- PMID 30931422.
- PMID 20584125.
- ^ U.S. Food and Drug Administration (10 February 2004). "FDA Updates Hormone Therapy Information for Post Menopausal Women". FDA News Release (Archived content). U.S. Food and Drug Administration. Retrieved 19 April 2013.
- PMID 12117397.
- PMID 18991792.
- PMID 18826989.
- ^ "For Women - Menopause and Hormones: Common Questions". Food and Drug Administration.
- PMID 20566620.
- S2CID 20401584.
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- ^ Harvard Women's Health Watch (August 2006). "What are bioidentical hormones?". Harvard Women's Health Watch. Retrieved 20 September 2014.
- S2CID 22844064.
- ^ Food and Drug Administration (28 June 2013). "FDA NEWS RELEASE: FDA approves the first non-hormonal treatment for hot flashes associated with menopause". FDA.
- ^ "Apo-Clonidine - Uses, Side Effects, Interactions - Drug Factsheets - C-Health". chealth.canoe.com. Archived from the original on 22 December 2015. Retrieved 21 December 2015.
- ^ "What Patients Need to Know About Hot Flashes". Medscape. (subscription required)
- PMID 17350196.
- PMID 10761538.
- S2CID 37254359.
- PMID 17289903.
- ^ PMID 17374837.
- ^ "Flaxseed in Treating Postmenopausal Women With Hot Flashes Who Have a History of Breast Cancer or Other Cancer or Who Do Not Wish to Take Estrogen Therapy". ClinicalTrials.gov. U.S. National Institute of Health. November 2010. Retrieved 20 April 2013.
- S2CID 9607095.
- S2CID 21847920.
- PMID 12804015.
- S2CID 25719669.
- PMID 36367692.
External links
- Hot flashes on Mayo Clinic website
- Hot Flashes on MedicineNet
- Hot Flushes on Patient.info