Hot flushes and night sweats explained

The flush experience

Hot flushes and night sweats are the same phenomenon happening at different times. Knowing the typical pattern helps you recognise them.

What a flush feels like

A wave of heat that spreads through the upper body and face, sometimes accompanied by sweating, a racing heart, mild dizziness or anxiety. Most flushes last 1 to 5 minutes. A cooling phase follows, sometimes with chills. Some women feel a flush coming on with a sense of warmth or unease. Others get no warning at all.

Night sweats

The same thing happening while you sleep. You wake up drenched, often having to change your night clothes and bedding. Sleep is disrupted, sometimes repeatedly across a single night. The cumulative effect of disturbed sleep over months or years drives a lot of the wider misery of menopause. Many women find night sweats more bothersome than daytime flushes.

How often they happen

Varies hugely. Some women have a few flushes a week. Others have them every hour. The frequency tends to be highest in late perimenopause and the first 1 to 2 years after menopause itself. For most women flushes gradually become less frequent after this peak, though some women have flushes for many years.

How long they last

On average flushes affect women for 7 to 10 years across perimenopause and after menopause. Some women have them for much shorter periods. Some have them for the rest of their lives. The variation is enormous. Many women find that even when flushes do not stop entirely they become much less troublesome over time.

Why your body does this

Hot flushes happen because the brain temporarily loses control of its temperature regulation. The reason is the dropping oestrogen levels of menopause.

The thermoregulatory zone narrows

Your hypothalamus normally maintains a comfortable temperature zone. Small fluctuations in body temperature within this zone do not trigger any response. Oestrogen helps maintain the width of this zone. As oestrogen drops the zone narrows dramatically. Tiny temperature increases that would have been ignored now trigger a full cooling response, which is the hot flush.

The cooling response

The flush is your body trying to cool you down. Blood vessels in the skin dilate, which is why you feel hot and may go red. Sweating starts to evaporate heat off your skin. Heart rate increases to pump more blood to the surface. The whole thing is a temperature regulation overreaction that would be appropriate if you were actually overheating. You are not.

Triggers

Several things commonly trigger flushes once the underlying mechanism is in place. Caffeine, alcohol, spicy food, hot drinks, stress, warm rooms and heavy bedding can all push you over the now narrow comfort threshold. Identifying your triggers helps you reduce frequency, though many flushes happen without obvious trigger.

Why some women are worse than others

Genetics, body weight, ethnicity, smoking history, mental health and various other factors influence flush severity. The reasons one woman has mild flushes while another struggles for years are not fully understood. The variation is real and biological rather than reflecting how women cope with symptoms.

Treatment options

Hot flushes have several effective treatments. The right choice depends on severity, personal medical history and preference. Speak to your GP about what suits you.

HRT works best

Hormone replacement therapy is by far the most effective treatment for hot flushes and night sweats. Most women see significant improvement within weeks of starting HRT. Many see complete resolution. For women whose lives are wrecked by flushes, HRT can be transformative. UK guidance supports HRT for women who want it and have no contraindications.

Non hormonal medication

Several non hormonal medications help. Certain antidepressants (SSRIs and SNRIs) reduce flush frequency for many women. Gabapentin can help. Clonidine works for some. These are options for women who cannot take HRT or prefer not to. The effect is typically less complete than HRT but worthwhile for many women.

CBT for menopausal symptoms

Cognitive behavioural therapy adapted for menopausal symptoms has good evidence for reducing the impact of flushes. CBT does not stop flushes happening but reduces how much they bother you. The effect on quality of life can be substantial. NHS services in some areas offer CBT for menopausal symptoms. Self help CBT books for menopause are also available.

Practical strategies

Layered clothing that you can easily remove. Keeping rooms cool. Sleeping with a fan. Cooling pillows and bedding. Avoiding triggers where possible. None of these stop the underlying mechanism but they reduce the disruption flushes cause. Most women combine practical strategies with whatever medical treatment they use.

Living with flushes

Even with the best treatment many women have some flushes for years. Knowing what to expect and how to manage the practical side helps.

Sleep is the priority

If flushes are wrecking your sleep, addressing them properly is not optional. Chronic poor sleep affects mood, cognitive function, immune function and almost everything else. Many women struggle for years before getting effective treatment because they think they should just push through. There is no medal for suffering. Speak to your GP.

Work and life adjustments

Flushes at work can be embarrassing and distracting. Many UK workplaces are now better at menopause support. Reasonable adjustments including more flexibility on temperature, access to fresh water and uniforms that are not too hot can help. The Faculty of Occupational Medicine has guidance on menopause at work that you can reference.

When to push for more help

If your first treatment is not working well, go back to your GP. Higher doses of HRT, different routes (changing from tablet to gel for example) or adding another treatment may help. Persistent severe flushes despite first line treatment may warrant referral to a menopause specialist. Many GP practices have menopause leads with extra training.

The longer view

Most women find flushes become less frequent and less disruptive over time. The peak years of flushes are usually the late forties and early fifties. By the late fifties and sixties most women have significantly fewer flushes. Some continue indefinitely but at a much milder level. The years of intense symptoms do not last forever even when they feel endless.

More on female health

For the broader transition our Menopause: A Complete Guide covers the life stage where flushes peak. Perimenopause: A Complete Guide covers the earlier phase. And Hormone Replacement Therapy: A Complete Guide covers the most effective treatment.