One minute you're fine; the next, a wave of heat climbs your chest and neck, your face flushes, and you're fanning yourself with whatever's nearest. At night, you wake up throwing off the duvet, damp and wide awake.
If this is you, you're in good company. Hot flushes and night sweats, known in the US as hot flashes and to doctors as vasomotor symptoms, are among the most common experiences of the menopause transition, and among the most treatable. Which makes the number of women told to put up with them harder to forgive.
Deep in your brain sits your internal thermostat, the hypothalamus. As oestrogen levels fluctuate and fall, this thermostat becomes more sensitive: its "comfortable" temperature range narrows. So a small rise in body heat that you'd never normally notice suddenly registers as "too hot," and your body slams on its cooling system. Blood vessels near the skin widen (the flush) and you sweat to cool down. It's not a malfunction so much as an over-reaction.
Researchers have since worked out the specific machinery, and it matters, because it is where the newest treatments come from. A small cluster of neurons in that thermostat responds to a brain chemical called neurokinin B, whose activity oestrogen normally keeps in check. Take the oestrogen away and those neurons become overactive, firing the cooling response at the smallest provocation. That is the flush, described at the level of the cell.
Most women expect a year or two. The research says otherwise.
Following thousands of women through the transition, the SWAN study found the median duration of frequent hot flushes was around seven and a half years. For women whose flushes began before their periods stopped, it was longer, often more than a decade. For women whose flushes started after the final period, it was shorter.
That is not written to frighten you. It is written because women who expect two years and get eight assume something is wrong with them, and because "just push through" is advice given by people who think this ends by Christmas.
Many women find flushes are set off by heat, spicy food, caffeine, alcohol (red wine is a frequent culprit), and stress. You can't always avoid them, but tracking your own pattern for a couple of weeks often reveals two or three reliable triggers you can dial down.
Smoking deserves its own line: it is associated with more frequent and more severe flushes, and with an earlier menopause. It is the one trigger where stopping changes more than the flush.
Be realistic about this layer. It takes the edge off. For frequent or severe flushes it will not be enough on its own, and no amount of layered clothing addresses the reason they are happening.
For flushes that are frequent or severe, this is treatable, and the options have grown considerably.
HRT remains the most effective treatment by a distance, and it treats the cause rather than the symptom. It also protects your bone. Its risks were badly misreported for twenty years, and a generation of women avoided it on the strength of headlines. The truth about HRT research sets out what the evidence actually says.
Non-hormonal medicines exist for women who cannot take HRT or would rather not: certain antidepressants at low doses, gabapentin, and clonidine among them. They are less effective than HRT and they work for many women.
The newest class targets the mechanism directly. Neurokinin receptor antagonists block the overactive brain pathway described above. Fezolinetant was approved in the US in 2023, and elinzanetant, which blocks a second receptor and may also help sleep, followed in 2025. These matter most for women who cannot take oestrogen at all, including many breast cancer survivors, for whom the options were thin.
They are not a free lunch. Fezolinetant carries a boxed warning for rare but serious liver injury, and liver blood tests are required before starting and at intervals through the first nine months. If you are prescribed it, that monitoring is not optional, and you should stop and seek advice at any sign of liver trouble: unusual tiredness, nausea, itching, dark urine, pale stools or yellowing of the eyes or skin.
Availability differs by country. The point is not that you should ask for a particular drug. The point is that the shelf is no longer bare, and "there's nothing for it" stopped being true some years ago.
Being honest here is more useful than being encouraging.
Black cohosh, evening primrose oil, red clover and most "menopause blends" perform poorly once trials are properly controlled, and the placebo response in flush studies is famously large, often 30% or more. That is why almost anything looks like it works in a testimonial and almost nothing survives a trial.
Soy and phytoestrogens are the most defensible of the group, with modest effects at best.
The wider picture is in supplements for women's hormones: what the evidence says. None of this means you must not try them. It means you should know what you are buying.
Two things sit underneath the discomfort.
Sleep. Night sweats fragment it, and broken sleep is what turns a manageable symptom into a life that feels unmanageable: the fog, the short fuse, the appetite, the lost will to train. Treat the sweats and much of that follows. How hormones hijack your sleep.
Your heart, possibly. Research has repeatedly found that women with frequent or persistent flushes tend to have less favourable cardiovascular markers. Whether flushes contribute to that risk or simply flag it is unsettled, and it is a reason to take frequent flushes seriously as information rather than only as an inconvenience. The heart-health shift every woman should know.
Flushing and sweats have other causes, and a few need excluding rather than assuming.
Drenching night sweats alongside unexplained weight loss, fever, or a persistent cough are a reason to see a doctor promptly, not a reason to buy a cooler duvet. An overactive thyroid produces heat intolerance and palpitations. Some medications flush. And in a woman under 40, flushes are not a symptom to manage; they are a symptom to investigate. See early menopause before 45.
If hot flushes are disrupting your sleep or your days, that's reason enough to take them seriously and to have a proper conversation about your options.
You do not have to grit your teeth and endure them as though there's nothing to be done. There is, there has been for decades, and there is more now than there was two years ago. The only part that has not improved is how often women are told to wait it out.
What triggers hot flushes?
Common triggers include heat, spicy food, caffeine, alcohol and stress. Smoking makes them more frequent and more severe. Tracking your own pattern for a fortnight usually reveals two or three you can act on.
What's the most effective treatment for hot flushes?
HRT, by a distance, and it treats the cause rather than the symptom. Non-hormonal medicines and the newer neurokinin receptor antagonists are options for women who cannot take it or would rather not.
How long do hot flushes last?
Longer than most women expect. Research following women through the transition found a median of around seven and a half years of frequent flushes, and longer for women whose flushes started before their periods stopped.
Can you have hot flushes before your periods stop?
Yes, and starting early tends to mean they last longer overall. Flushes usually become more prominent in the late transition, once gaps of 60 days or more appear between periods.
Do supplements help hot flushes?
Mostly not, once trials control for placebo, which in flush research is unusually powerful. Soy and phytoestrogens are the most defensible, with modest effects.
Are night sweats always menopause?
No. Drenching sweats with weight loss, fever or a persistent cough need a doctor rather than a fan. An overactive thyroid and some medications also cause them.
Sources: Avis NE et al., duration of vasomotor symptoms over the menopause transition (SWAN), JAMA Intern Med 2015;175(4):531-9 · NICE NG23, Menopause: diagnosis and management · US Food and Drug Administration, Drug Safety Communication and Boxed Warning, fezolinetant (Veozah), 2024 · Educational only, not medical advice. Availability and licensing of medicines differ by country.
Keep reading: The truth about HRT · How hormones hijack your sleep · Supplements: what the evidence says · The heart-health shift · Find your menopause stage (free) · Take the free Hormone Quiz