Last checked September 2026 against 12 sources · Editorial policy
Hot flashes: causes, triggers and treatments
A hot flash is a sudden wave of heat through the face, neck and chest, often with sweating, flushing and a racing heart. It lasts several minutes and can leave you cold afterwards. Between 50% and 75% of women get hot flashes or night sweats during the menopause transition. They start in the brain's temperature center, and they are very treatable.
A hot flash is a sudden wave of heat, flushing and sweat that usually lasts a few minutes. Why they happen, common triggers, and treatments that work.
Video: Hot flashes: why they happen, how long they last, and what actually helps
Read the transcript (728 words)▾
Four oh five. Checkout line. And then my face is on fire. That's a hot flash. Most women get them in the transition. Here's what's actually happening in your body, how long they last, and what the research says helps.
A hot flash is a sudden wave of heat through the face, neck and chest. Your skin flushes, you may sweat heavily, and your heart can race. It usually lasts a few minutes, and when the sweat cools, you can end up cold and shivery. Night sweats are the same thing, happening while you sleep.
It starts in the brain. Deep inside it, the hypothalamus works like a thermostat, and estrogen helps keep its comfortable range wide. As estrogen swings and falls, a group of nerve cells that use a messenger called neurokinin B becomes overactive. The comfortable range narrows. A tiny rise in body temperature, one you'd normally never notice, gets read as overheating. So your body dumps heat, fast. Blood vessels in the skin open, sweat starts, the heart speeds up. That's the flash. It's also why one of the newest non-hormonal medicines works by blocking neurokinin B instead of replacing estrogen.
Between fifty and seventy-five percent of women get hot flashes or night sweats during the transition, and a 2023 review puts it as high as eighty-seven percent at some point. In SWAN, frequent hot flashes lasted a median of seven point four years in total, and four and a half years after the final period. If they started early in the transition, the median was more than eleven point eight years. African American women had the longest course, a median of ten point one years. Women whose hot flashes only began after menopause had the shortest, three point four years.
At night, the same flash plays out in the dark. A wave of heat wakes you, you sweat through your nightclothes, then you're cold and wide awake. In SWAN, women with more frequent hot flashes had higher odds of every kind of sleep trouble, so night sweats are one of the main reasons sleep breaks down in perimenopause. A cool bedroom and breathable bedding help with comfort. For the sleep itself, cognitive behavioral therapy for insomnia has strong evidence: in a trial of women with hot flashes, eighty-four percent were in the no-insomnia range six months later, compared with forty-three percent who got education alone.
In the moment, a few simple things help: light layers you can take off, a fan, a cold drink, a cool shower, a cool bedroom at night. Spicy food, caffeine, hot drinks, alcohol and smoking are common triggers, so cutting back can help. Keeping to a healthy weight is also advised. None of these switch hot flashes off, but they can take the edge off.
Hormone therapy is the most effective option. Estrogen cuts hot flash frequency by about seventy-five percent, and tablets and patches work equally well. If you still have a uterus, estrogen is combined with a progestogen to protect its lining. For healthy women under sixty, or within ten years of their last period, the benefits generally outweigh the risks. Fezolinetant, a daily non-hormonal pill that blocks neurokinin B, is recommended at the highest level of evidence by the Menopause Society, and by UK guidelines when hormone therapy isn't suitable. Certain antidepressants and gabapentin reduce hot flashes by about forty to sixty-five percent, and oxybutynin, a bladder medicine, is also recommended. These are useful if you can't take hormones. Cognitive behavioral therapy and clinical hypnosis work less on the heat itself and more on how much hot flashes bother you, and on your sleep. And what the 2023 review didn't find support for: supplements and herbal remedies, soy, acupuncture, yoga and paced breathing.
Some sweats need a different explanation. Sweats with a fever, a cough, diarrhea or weight loss you can't explain. Feeling hot all the time rather than in waves, with shaky hands and a fast heartbeat at rest, which can point to an overactive thyroid. Sweating that started with a new medicine. Or hot flashes that appear for the first time many years after menopause. All of these deserve a doctor's look.
Hot flashes are common, they can last for years, and there are options that work at any stage. Find your stage in two minutes at perimenostage.com, and bring it to your doctor.
Every number in this video is sourced in the YouTube description.
Hot flashes: what women expect vs what research shows
What people often expect
“A few months of flushes around your last period”
What the evidence shows
In SWAN, the largest US study of the transition, frequent hot flashes lasted a median of 7.4 years in total and carried on for a median of 4.5 years after the final period. Women whose flushes started early, while periods were still regular or only starting to change, had the longest course: a median of more than 11.8 years. The researchers' advice to doctors was blunt: tell women to expect frequent hot flashes to last more than 7 years.
What causes hot flashes?
Hot flashes start in the brain's thermostat
Estrogen keeps the brain's thermostat, in the hypothalamus, running with a comfortable margin. As estrogen swings and falls in perimenopause, a group of nerve cells that release a messenger called neurokinin B becomes overactive. The thermostat's safe zone narrows, so a small rise in core temperature that you would normally never notice is read as overheating. This is why the newest non-hormonal hot flash drugs work by blocking neurokinin B signals rather than by replacing estrogen.
What happens in your body during a hot flash
Once the thermostat decides you're too hot, your body dumps heat fast. Blood vessels in the skin widen, which is the red flush over the face, neck and chest. You sweat, and your heart speeds up. The NHS describes a hot flash as the face, neck and chest suddenly feeling very hot, sometimes with heavy sweating, palpitations, anxiety or dizziness, lasting several minutes. When the sweat evaporates, you can swing to feeling cold and shivery.
Why hot flashes happen at night
Night sweats are the same hot flashes during sleep. The same cascade wakes you up soaked, sometimes several times a night. SWAN found that women with more frequent hot flashes had more trouble falling asleep, staying asleep and waking too early. That is why tiredness, irritability and brain fog so often travel with hot flashes: the daytime symptoms are partly the cost of broken nights, and they usually improve when the flashes are treated.
Common hot flash triggers
Individual flashes can be set off by triggers. The NHS lists spicy food, caffeine, hot drinks, smoking and alcohol, plus stress. A warm room, heavy bedding and layers that trap heat make things worse. Triggers don't cause the underlying problem, which is the narrowed thermostat, and The Menopause Society's 2023 review found that avoiding triggers hasn't been shown to reduce how often hot flashes happen. Knowing yours can still make individual episodes easier to live with.
Who has hot flashes the longest
Hot flashes last longer for some women than others. In SWAN, African American women had the longest total duration, a median of 10.1 years, and the NHS notes that women from a Black ethnic background are more likely to have hot flashes that are severe and continue longer. Starting hot flashes at a younger age, higher stress, greater sensitivity to symptoms, and more depressive symptoms and anxiety when flashes first began were also linked with a longer course.
Hot flashes also happen outside menopause
Menopause is the most common reason for hot flashes and night sweats in midlife, but not the only one. The NHS lists anxiety, some antidepressants, steroids and painkillers, low blood sugar, alcohol or drug use, and hyperhidrosis, a harmless condition that makes you sweat too much all the time. Sometimes no cause is found. If your flashes don't fit the menopause pattern, the section below shows what else to check.
How common are menopause hot flashes?
From the studies on this page
of women have hot flashes, night sweats or both during the menopause transition
50–75%
Reported range across studies or subgroups
of women report hot flashes during or after the menopause transition, according to a 2023 review
Up to 87%
median total duration of frequent hot flashes in SWAN, a study that followed 3,302 women at 7 US sites
7.4 years
Bar scaled to a 12-year reference span
median duration for African American women, the longest of any ethnic group in the study
10.1 years
Bar scaled to a 12-year reference span
11.8+ years
Figures vary because studies define hot flashes differently: some count any flush, others only frequent ones. Either way, hot flashes are the most typical symptom of the transition, and most women who get them have them for years, not months.
Hot flashes that aren't menopause
Menopause is the most common reason for sudden heat and sweating in midlife, but it isn't the only one. These causes look similar, and each has a clue that sets it apart.
Overactive thyroid
Check →Feeling hot most of the time rather than in waves, with weight loss, shaky hands, a fast heartbeat at rest, restlessness and irritability.
Test: TSH blood test
A medicine
Check →Sweating started or got worse after a new medicine. Some antidepressants, steroids and painkillers are common culprits.
Test: Medicine review with a doctor or pharmacist
Infection or other illness
Sweats with a very high temperature, feeling hot, cold or shivery, a cough or diarrhea, or weight loss you can't explain.
Test: Doctor's assessment
Low blood sugar or alcohol
Sweats after skipped meals, on diabetes medicine, or after drinking. They come with shakiness or hunger rather than a wave of heat.
Test: Blood sugar check if you take diabetes medicine
Anxiety
Check →Sweating and a pounding heart come with worry, dread or panic, and the heat isn't the first thing you notice.
Test: Doctor's assessment
Hyperhidrosis
You sweat too much all the time, not in sudden waves with heat, and it started long before perimenopause.
Test: Doctor's assessment
Hot flash treatment: what works and what doesn't
HRT for hot flashes
Strong evidenceEstrogen, alone or with a progestogen, is the first-line treatment and cuts hot flash frequency by about 75%. Tablets and patches work equally well. NICE advises offering HRT for hot flashes, and The Menopause Society calls hormone therapy the most effective treatment, to be considered for women within 10 years of their final period. If you still have a uterus, estrogen is combined with a progestogen to protect its lining.
Related guide →Fezolinetant (Veozah), a non-hormonal hot flash pill
Strong evidenceA daily pill that blocks neurokinin B signals in the brain's thermostat, the switch that sets off hot flashes. The Menopause Society's 2023 review recommends it at its highest level of evidence, and NICE recommends it for moderate to severe hot flashes when HRT is unsuitable. It is one of the main options for women who can't take estrogen, for example after an estrogen-dependent cancer, or who prefer not to.
Related guide →SSRIs, SNRIs and gabapentin for hot flashes
Strong evidenceParoxetine, venlafaxine, desvenlafaxine, escitalopram, citalopram and gabapentin reduce hot flash frequency by about 40–65%. Oxybutynin, a bladder medicine, is also recommended. These are useful if you can't take hormones. NICE says not to offer SSRIs, SNRIs or clonidine routinely as the first choice for hot flashes alone, so they usually come second, after HRT has been discussed.
Related guide →CBT and clinical hypnosis for hot flashes
Strong evidenceBoth are recommended at the highest level of evidence in The Menopause Society's 2023 review. They work less on the heat itself and more on how much hot flashes bother you and how they affect your sleep. NICE suggests menopause-specific CBT for hot flashes, either alongside HRT or for women who can't or don't want to take it.
Related guide →Weight loss and hot flashes
Some evidenceThe Menopause Society's 2023 review recommends weight loss for hot flashes, based on limited evidence and expert consensus. The NHS also advises keeping to a healthy weight as part of managing hot flashes. It's slower than medicine, but it lowers other midlife health risks at the same time.
How to stop a hot flash fast
First stepTo get through a hot flash quickly: wear light layers you can take off, keep a fan and a cold drink nearby, take a cool shower, and keep your bedroom cool at night. Cutting back on spicy food, caffeine, hot drinks, smoking and alcohol removes common triggers. These make each episode more bearable, but they haven't been shown to reduce how many hot flashes you have, so if flashes are frequent, treatment is the next step.
Supplements, soy and acupuncture for hot flashes
No good evidenceThe Menopause Society's 2023 review doesn't recommend supplements and herbal remedies, soy foods and extracts, acupuncture, yoga, paced breathing or cannabinoids for hot flashes. NICE notes some evidence for isoflavones and black cohosh, but warns that preparations vary, their safety is uncertain, and interactions with other medicines have been reported.
Related guide →
When to see a doctor about hot flashes
Urgent: Chest pain, breathlessness or fainting with a racing heart
Call 911 (999 in the UK) if palpitations don't go away or come with chest pain, shortness of breath or fainting. Don't drive yourself.
Hot flashes with fever, cough or weight loss
See a doctor. Sweats with a high temperature, a cough, diarrhea or unexplained weight loss point away from menopause and need checking.
Hot flashes wake you or wreck your days
You don't need to wait them out. HRT and non-hormonal medicines work, and a doctor can prescribe them. NICE advises offering HRT for hot flashes.
Hot flashes and period changes before 40
See a doctor. This can be premature ovarian insufficiency, which NICE advises diagnosing with FSH blood tests taken 4 to 6 weeks apart.
Hot flashes: frequently asked questions
What is a hot flash?
A hot flash is a sudden feeling of heat in the face, neck and chest that lasts several minutes, often with sweating, flushing, a pounding heart, anxiety or dizziness, and sometimes a chill afterwards. When it happens during sleep, it's called a night sweat. Hot flashes are the most typical symptom of the menopause transition, affecting 50% to 75% of women.
What do hot flashes feel like?
Most women describe a rush of heat that starts in the chest or face and spreads upward, with red skin, sweat and a racing heart. Some feel a wave of anxiety or dizziness first. As the sweat evaporates you can go cold and shivery. Our guide to what a hot flash feels like covers chills, cold flashes and hot flashes in the face.
Related →How long does a hot flash last?
A single hot flash usually lasts several minutes. Over the years, frequent hot flashes lasted a median of 7.4 years in total in SWAN, including a median of 4.5 years after the final period. Women whose flashes started early in perimenopause had them longest.
Related →What causes hot flashes?
Swinging and falling estrogen makes the brain's thermostat oversensitive, so small rises in core temperature trigger a heat-release response. Spicy food, caffeine, hot drinks, smoking, alcohol and stress can set off individual flashes. Outside menopause, some medicines, anxiety, low blood sugar and infections also cause flushing and sweats.
How do you stop hot flashes fast?
In the moment, take off a layer, use a fan, sip a cold drink or take a cool shower. That makes each flash easier but won't reduce how often they come. To actually stop hot flashes, the most effective option is HRT, which cuts frequency by about 75%. Fezolinetant, SSRIs, SNRIs, gabapentin and CBT are proven alternatives if you can't take hormones.
Can you get hot flashes before your periods stop?
Yes. They often start in perimenopause while you still have periods, sometimes while cycles are still regular. Women whose hot flashes began before or early in the transition had them longest in SWAN: a median of more than 11.8 years in total, and 9.4 years after the final period.
Do hot flashes ever stop?
For most women, yes. In SWAN the median was 7.4 years in total and 4.5 years after the final period. Women who only started having them after menopause had the shortest run, a median of 3.4 years. A minority keep having them for much longer, and treatment works at any age.
What is the most effective hot flash treatment?
HRT. Estrogen reduces hot flash frequency by about 75%, and tablets and patches work equally well. If you can't or don't want to take hormones, fezolinetant, SSRIs, SNRIs, gabapentin, oxybutynin, CBT and clinical hypnosis all have good evidence. Non-hormonal medicines cut frequency by about 40% to 65%.
Are hot flashes a sign of menopause?
Usually, yes, especially in your 40s and 50s alongside changes in your periods. But hot flashes can also come from an overactive thyroid, some medicines, anxiety, low blood sugar or infection. See a doctor if they come with fever, weight loss or a racing heart at rest, or if they start before 40.
Sources
- Crandall CJ, Mehta JM, Manson JE. Management of Menopausal Symptoms: A Review. JAMA. 2023;329(5):405-420.
- NHS. Symptoms of menopause and perimenopause.
- Avis NE, Crawford SL, Greendale G, et al. Duration of menopausal vasomotor symptoms over the menopause transition. JAMA Intern Med. 2015;175(4):531-9.
- Conklin M, Santoro N. Neurokinin receptor antagonists as potential non-hormonal treatments for vasomotor symptoms of menopause. Ther Adv Reprod Health. 2023;17:26334941231177611.
- Kravitz HM, Zhao X, Bromberger JT, et al. Sleep disturbance during the menopausal transition in a multi-ethnic community sample of women. Sleep. 2008;31(7):979-90.
- NHS. Things you can do to help menopause and perimenopause symptoms.
- The North American Menopause Society. The 2023 nonhormone therapy position statement of The North American Menopause Society. Menopause. 2023;30(6):573-590.
- NHS. Night sweats.
- NHS. Tiredness and fatigue.
- NICE. Menopause: identification and management (NG23). Updated 2024.
- NHS. Heart palpitations.
- National 911 Program. 911.gov.
See our editorial policy.
Related symptoms
Night sweats in perimenopause and menopause
Night sweats are hot flashes during sleep. Why falling estrogen triggers them, bedroom and lifestyle fixes, an…
What does a hot flash feel like?
Sudden heat rising through the chest, neck and face, flushing, sweating, a racing heart, then chills. What a h…
How long do hot flashes last?
Each hot flash lasts a few minutes. Overall, hot flashes continue for about 7 years on average, and over 10 ye…
Heart palpitations in perimenopause
A racing, fluttering or pounding heart is common in perimenopause and often harmless. What causes it, how to c…