Hot flashes

Key Facts

• Hot flashes affect approximately 80% of women going through menopause, making them the single most common symptom
• Each episode typically lasts 1 to 5 minutes, though it can feel much longer
• The SWAN study found that frequent hot flashes last a median of 7.4 years, and for some women, more than a decade
• Hot flashes that happen at night are called night sweats, and they're the same phenomenon with the same underlying cause
• Hormone therapy (HRT) is the most effective treatment, but several non-hormonal options now exist, including two medications approved since 2023
• Tracking your hot flashes (when they happen, what triggered them, how severe they are) can help you and your doctor find the right approach

What are hot flashes?

If you've ever felt a sudden wave of heat sweep through your body, your face flushing red, your heart picking up speed, sweat appearing on your chest and neck out of nowhere, you already know what a hot flash is. And if this has been happening to you more and more often, you're not imagining it, you're not overreacting, and you are very much not alone.

Hot flashes (sometimes called hot flushes) are the hallmark symptom of menopause. They're classified medically as "vasomotor symptoms" because they involve your blood vessels dilating rapidly, which sends a rush of blood to the skin's surface. That's what creates the sensation of intense heat, the visible flushing, and the sweating that follows. Some women also experience a rapid heartbeat, tingling in the fingers, or a wave of anxiety just before or during an episode.

A single hot flash typically lasts between 1 and 5 minutes, though the aftereffects (feeling overheated, clammy, or drained) can linger longer. Some women get a few mild ones a week. Others experience 10 or more a day, severe enough to disrupt work, sleep, and social life. There is an enormous range in how women experience this, and all of it is normal.

When hot flashes happen during sleep, they're called night sweats. The mechanism is identical, but the impact on your life can be different: waking up drenched in sweat several times a night takes a serious toll on sleep quality, energy, and mood. Night sweats are often one of the earliest signs of perimenopause, partly because estrogen levels tend to dip lowest during the night.

What does it feel like?

The experience is surprisingly hard to put into words for something so common. Women in research studies and online forums describe it in dozens of ways: "a furnace switching on inside my chest", "like someone poured hot water under my skin", "my face goes bright red and I can feel the heat radiating off me."

A typical episode starts with a sudden sensation of warmth in the chest or abdomen that rises rapidly to the neck and face. The skin may flush visibly, especially on the cheeks, neck, and upper chest. Sweating follows, sometimes light, sometimes drenching. Some women notice their heart racing or pounding. A few experience a brief moment of anxiety or even dread just before the heat arrives, which researchers believe is related to the same brain signal that triggers the flash itself.

After the heat passes, many women feel chilled as the sweat evaporates. This hot-to-cold swing can happen in minutes and it's particularly disorienting when it catches you in the middle of a meeting, on public transport, or trying to fall asleep.

The severity varies enormously. For some women, hot flashes are a mild inconvenience, a brief flush that comes and goes. For others, they're genuinely debilitating: severe hot flashes have been associated with higher rates of anxiety, depression, and significantly reduced quality of life. If yours are on the more severe end, that's not a failure of coping. It reflects differences in your individual biology, not in your character.

Why it happens

For decades, doctors knew that hot flashes were connected to declining estrogen levels but couldn't fully explain the mechanism. That picture has become much clearer in recent years, thanks to the discovery of a group of specialised brain cells called KNDy neurons.

Here's what's happening inside your body:

Your brain has a built-in thermostat, located in a region called the hypothalamus. This thermostat constantly monitors your core temperature and triggers cooling responses (sweating, blood vessel dilation) or warming responses (shivering, blood vessel constriction) to keep you within a narrow comfort zone, sometimes called the thermoneutral zone.

In the same neighbourhood of the hypothalamus, there are KNDy neurons (named after the three chemicals they produce: kisspeptin, neurokinin B, and dynorphin). These neurons have two jobs: they help regulate reproductive hormones, and they communicate with the thermostat.

When estrogen levels are stable, these neurons behave calmly. But when estrogen drops, as it does during perimenopause and menopause, KNDy neurons become hyperactive. They swell in size and start firing excessively. That overactivity spills into the neighbouring thermoregulatory centre, essentially confusing your thermostat. Your brain thinks you're overheating, even though your actual body temperature is perfectly normal, and it launches a full cooling response: blood vessels dilate, sweat glands activate, and you experience a hot flash.

This is why hormone therapy works so well for hot flashes: restoring estrogen calms the KNDy neurons back down. It's also why the newest non-hormonal treatments (fezolinetant and elinzanetant) work: they block the neurokinin receptors that KNDy neurons use to communicate with the thermostat, interrupting the false alarm at its source.

How long do they last?

One of the most frustrating things about hot flashes is the uncertainty. "How long will this go on?" is one of the first questions women ask, and the honest answer is: it varies widely.

The landmark SWAN (Study of Women's Health Across the Nation) study followed thousands of women over many years and found that frequent hot flashes last a median of 7.4 years. But averages don't tell the whole story:

• Women whose hot flashes began during early perimenopause (while still having regular periods) experienced them for a median of 11.8 years
• Women whose hot flashes didn't start until after their final period had a median duration of 3.4 years
• About 30% of women still experienced hot flashes 10 to 19 years after menopause
• Duration also varied by race and ethnicity: Black women in the study experienced the longest duration (an average of over 11 years), while Japanese and Chinese women averaged about half that

Factors associated with longer duration include smoking, higher body weight, stress, anxiety, and depression. This doesn't mean those things cause hot flashes, but they appear to make the thermoregulatory system more reactive.

The takeaway: for most women, hot flashes do eventually diminish. But "just wait it out" is not a reasonable strategy when symptoms are affecting your quality of life. Treatment exists for a reason.

What you can do

There are practical, evidence-based things you can do that make a genuine difference. Some are about reducing triggers, others about building resilience.

Know your triggers. Hot flashes don't always strike randomly. Common triggers include alcohol (especially red wine), spicy foods, caffeine, hot drinks, warm rooms, stress, and tight clothing. Not every trigger affects every woman, which is why tracking is valuable. Keeping a log of when hot flashes happen and what preceded them can reveal your personal patterns within a few weeks.

Dress in layers. It sounds simple because it is. Wearing layers that you can quickly remove (a cardigan over a breathable cotton top, for example) gives you control when a flash hits. Choose natural fibres like cotton or moisture-wicking fabrics. Avoid synthetic fabrics that trap heat.

Cool your sleeping environment. Night sweats are often the most disruptive part of this. Keep your bedroom cool (around 18°C / 65°F), use breathable cotton or bamboo bedding, and consider a fan or cooling pillow. Some women keep a cold water bottle on the nightstand.

Manage stress actively. Stress doesn't just feel bad, it directly affects the hypothalamic system that triggers hot flashes. Cognitive behavioural therapy (CBT) has strong evidence for reducing how much hot flashes bother you: the NICE guidelines specifically recommend it as an option. Regular mindfulness practice and breathing exercises can also help.

Stay physically active. While exercise itself won't eliminate hot flashes (NAMS notes the evidence for exercise alone is limited), regular aerobic activity improves sleep, reduces stress, supports cardiovascular health, and helps maintain a healthy weight, all of which contribute to managing the overall picture. Aim for at least 150 minutes of moderate activity per week.

Maintain a healthy weight. Research consistently shows that women with higher body weight tend to experience more frequent and severe hot flashes. Even modest weight loss (5-10%) has been associated with improvement in some studies.

Treatment options

If self-care measures aren't enough, and for many women they won't be, there are effective medical treatments. This is not about willpower or trying harder. Some women's hot flashes are simply too frequent or too severe to manage without medication, and seeking treatment is a completely reasonable choice.

Hormone therapy (HRT)

Hormone therapy remains the gold standard for treating hot flashes. It is the most effective treatment available and works by replenishing the estrogen that your body is producing less of, which calms the hyperactive KNDy neurons and restores normal thermoregulation.

HRT comes in several forms: patches, gels, sprays, and tablets. Women who still have a uterus take a combined form (estrogen plus progesterone) to protect the uterine lining. Your doctor will help determine the right type and dose.

HRT is generally recommended for women under 60 or within 10 years of their final period, where the benefits clearly outweigh the risks for most women. The decision is individual and should account for your medical history, symptom severity, and personal preferences.

Non-hormonal medications

For women who can't or prefer not to use HRT, there are now genuinely effective alternatives:

Fezolinetant (Veozah), approved by the FDA in 2023, was the first medication to target the KNDy neuron pathway directly. It blocks the NK3 receptor, interrupting the false overheating signal at its source. It's effective for moderate to severe hot flashes. An important note: the FDA added a boxed warning in late 2024 about a rare risk of serious liver injury, so liver function monitoring is required.

Elinzanetant (Lynkuet), approved in October 2025, is a dual NK1/NK3 receptor antagonist. In clinical trials, it reduced the frequency of moderate to severe hot flashes by about 74% at 12 weeks. It also appears to improve sleep, which makes it particularly interesting for women whose hot flashes and night sweats are disrupting rest.

SSRIs and SNRIs (antidepressants like paroxetine, venlafaxine, and escitalopram) can reduce hot flash frequency by roughly 20-60%. Paroxetine is the only SSRI with specific FDA approval for hot flashes. These can be a good option for women who also experience mood symptoms.

Gabapentin, originally developed for seizures, has shown benefit for hot flashes, especially nighttime episodes. It can cause drowsiness, which some women actually find helpful for sleep.

What about supplements and herbal remedies?

This is where honesty matters. Black cohosh, red clover, evening primrose oil, and soy isoflavone supplements are widely marketed for hot flashes. The scientific evidence for most of these is weak to nonexistent. NAMS's 2023 position statement specifically notes that supplements and herbal remedies are not recommended based on current evidence.

That doesn't mean no woman has ever felt better taking them, but it does mean that if your hot flashes are significantly affecting your life, evidence-based treatments are more likely to help. If you want to try supplements, discuss them with your doctor first, particularly because some can interact with other medications.

When to see a doctor

Hot flashes are a normal part of menopause, but "normal" doesn't mean you have to suffer through them. Consider seeing your doctor if:

• Hot flashes are disrupting your sleep regularly (waking you multiple times per night)
• They're interfering with your work, relationships, or daily activities
• You're experiencing significant anxiety or low mood alongside them
• You're having more than 7 to 10 moderate-to-severe episodes per day
• They started suddenly and you're under 45 (this may indicate early menopause, which warrants evaluation)
• You're unsure whether what you're experiencing is menopause-related or something else

What to bring to your appointment: A log of your symptoms is incredibly useful. Note how often hot flashes happen, how severe they are (mild, moderate, severe), what time of day, any triggers you've noticed, and how they're affecting your sleep and daily life. This information helps your doctor recommend the right treatment much faster.

Don't feel you need to downplay your symptoms. If hot flashes are affecting your quality of life, that is reason enough to seek help. You deserve to feel comfortable in your own body.

How Menovita can help

Menovita is designed to help you track exactly the kind of information your doctor needs: hot flash frequency, severity, timing, and triggers. Over time, the app helps you spot patterns you might not notice on your own (maybe your hot flashes are worse after certain foods, or cluster at specific times of day). When it's time for a doctor's visit, you'll have clear data to share rather than trying to remember weeks of symptoms from memory.

Frequently Asked Questions

Are hot flashes dangerous?

Hot flashes themselves are not dangerous, but recent research suggests that women who experience frequent, persistent hot flashes may have a somewhat higher risk of cardiovascular disease over time. This is another reason why managing severe symptoms (rather than just enduring them) is worthwhile, and why maintaining heart-healthy habits during menopause matters.

Can men get hot flashes?

Yes. Men undergoing androgen deprivation therapy for prostate cancer commonly experience hot flashes. Some men also experience them during natural age-related testosterone decline (sometimes called andropause), though this is less common and usually less severe than in women.

Do hot flashes mean I'm in menopause?

Not necessarily. Hot flashes often begin during perimenopause, which can start years before your final period. They're one of the earliest signs that your hormones are shifting. If you're in your 40s and noticing hot flashes but still getting periods, you're likely in perimenopause.

Will losing weight help my hot flashes?

Possibly. Several studies have found that women with higher body weight tend to have more frequent and severe hot flashes, and that weight loss can improve symptoms. However, weight is just one factor among many, and thin women certainly get hot flashes too. It's worth pursuing for overall health, but it's not a guaranteed fix.

Is it safe to take HRT for hot flashes?

For most women under 60, or within 10 years of their final period, the benefits of HRT for bothersome hot flashes outweigh the risks. The risk profile depends on your individual health history (particularly regarding breast cancer, blood clots, and cardiovascular disease). This is a conversation to have with your doctor, who can assess your personal risk factors. Both NAMS and NICE support HRT as a first-line treatment for moderate to severe vasomotor symptoms.