Hot flushes and night sweats: how long they last and what the guidelines say

A hot flush is a sudden feeling of heat in the face, neck and chest, often with visible flushing, sweating, palpitations and real physical discomfort, lasting several minutes ³. At night the same event is called a night sweat, and it usually wakes you.

Clinically both are grouped as vasomotor symptoms. Up to 80% of women experience them during the transition, and most rate them as moderate to severe ¹.

How long they last

This is where most women have been misinformed, usually with the phrase "a year or two".

The Study of Women's Health Across the Nation followed 3,302 women at seven US sites from 1996 to 2013. Among 1,449 women who reported frequent vasomotor symptoms, defined as hot flushes or night sweats on at least six days in the previous two weeks, the median total duration was 7.4 years ¹.

For the 881 women whose final menstrual period could be dated, symptoms persisted a median of 4.5 years after that period ¹.

The variation within that average is the useful part.

The strongest single predictor of a long run was starting early. Women who were premenopausal or early perimenopausal when they first reported frequent symptoms had a median total duration of more than 11.8 years, and a median of 9.4 years of persistence after their final period ¹. Women whose symptoms only began after menopause had the shortest course, a median of 3.4 years ¹.

Duration also differed markedly by ethnicity. Median total duration was 10.1 years in African American women, 8.9 years in Hispanic women, 6.5 years in non-Hispanic white women, 5.4 years in Chinese women and 4.8 years in Japanese women ¹. The physiological reasons for these differences are not known ¹. The NHS makes a related point about severity, noting that women from a Black ethnic background are more likely to have hot flushes that are severe and continue longer ².

Other factors associated with a longer course were younger age at first report, lower educational level, greater perceived stress, higher symptom sensitivity, and depressive or anxiety symptoms at the time symptoms began ¹.

The SWAN authors' own conclusion was blunt: clinicians should counsel women to expect that frequent vasomotor symptoms could last more than seven years ¹.

Two things follow from that. First, if you have been quietly waiting this out on the assumption it ends soon, the data does not support the assumption. Second, "it will pass" may take longer than you were told, which is worth knowing if you are deciding whether to talk to a clinician about the options.

Why they cluster when they do

STRAW+10 notes that oestradiol keeps falling and FSH keeps rising for roughly two years after the final period before levels stabilise, and that vasomotor symptoms are most likely to occur during that stage ⁷. That is the mismatch behind a very common experience: periods stopped, and then things got worse.

What guidelines say about options

Nobody writing here is going to tell you what to take. That decision belongs to you and a clinician who knows your history, your risk factors and what you actually want. What follows is what the major guidelines say, so you can walk in knowing what is on the table.

Hormone therapy

Both major guidelines put it first for effectiveness. NICE recommends offering HRT to people with vasomotor symptoms associated with menopause ⁴. The Menopause Society states that hormone therapy remains the most effective treatment for vasomotor symptoms and for the genitourinary syndrome of menopause, and that for women under 60 or within ten years of menopause onset with no contraindications, the benefit-risk balance is favourable for treating bothersome vasomotor symptoms and preventing bone loss ⁶.

Both are equally clear that risk depends on the specifics: type, dose, duration, route of administration, timing of initiation, and whether a progestogen is used ⁶. There is a separate article on this site covering the benefit and risk tables in detail.

Cognitive behavioural therapy

NICE recommends considering menopause-specific CBT as an option for vasomotor symptoms ⁴. The Menopause Society also lists cognitive-behavioral therapy as recommended at Level I, meaning good and consistent scientific evidence, alongside clinical hypnosis ⁵.

This is not a consolation prize offered because someone thinks the flushes are in your head. CBT for vasomotor symptoms targets the response to the event, and the evidence for it is graded as strongly as the evidence for several prescription options.

Prescription non-hormonal options

The Menopause Society recommends, at Level I, selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors, gabapentin, and fezolinetant. Oxybutynin is recommended at Levels I to II, and weight loss and stellate ganglion block at Levels II to III ⁵.

NICE lists fezolinetant as an option for moderate to severe vasomotor symptoms when HRT is unsuitable, referring to its 2026 technology appraisal ⁴.

Where the two guidelines disagree

This is worth knowing before you go in, because you may hear either position.

On antidepressants, NICE says do not routinely offer SSRIs, SNRIs or clonidine as first-line treatment for vasomotor symptoms alone ⁴. The Menopause Society recommends SSRIs and SNRIs as non-hormone options at Level I ⁵. These are not contradictory statements about whether the drugs work; they are different judgements about where in the sequence they belong. A clinician following NICE is likely to discuss HRT or CBT first.

On lifestyle measures, the disagreement is sharper. The Menopause Society's 2023 review explicitly does not recommend paced respiration, cooling techniques, avoiding triggers, exercise, yoga, mindfulness-based intervention, relaxation, soy foods and soy extracts, the soy metabolite equol, cannabinoids, or acupuncture for treating vasomotor symptoms, based on the evidence for each ⁵. That is a striking list, and it is at odds with a great deal of general advice.

It is worth reading carefully what that means. It means these measures have not shown a reliable effect on flush frequency or severity in trials. It does not mean exercise is bad for you, and both guidelines recommend physical activity for other reasons, including muscle mass and bone health ⁴.

Supplements and herbal products

The Menopause Society does not recommend supplements or herbal remedies for vasomotor symptoms, graded Levels I to II ⁵.

NICE is more granular. It says there is some evidence that isoflavones or black cohosh may relieve vasomotor symptoms, while requiring clinicians to explain the caveats, including that multiple preparations are available with varying ingredients and that the safety, quality and purity of unregulated preparations may be unknown ⁴. NICE also says the efficacy and safety of unregulated hormone preparations are unknown ⁴, and adds a specific warning for women with a personal history of or at high risk of breast cancer about uncertainty around St John's wort ⁴.

The NHS puts it more directly: there is very little evidence for how well herbal remedies and complementary medicines work or how safe they are, and some may cause serious side effects when taken with other medicines ⁸.

This is why interactions, rather than cost, are the main reason guidance wants clinicians to know about anything taken over the counter ⁸.

Guidance in the US and Europe

In the US, where they are usually called hot flashes, the FDA approved elinzanetant (Lynkuet) in October 2025 to reduce moderate to severe hot flashes due to menopause. In trials it reduced how often and how severely they happened compared with a placebo ¹⁰. Fezolinetant, sold in the US as Veozah, carries a boxed warning added in December 2024 about rare but serious liver injury, with liver blood tests before starting, monthly for the first three months, and then at months 6 and 9 ¹¹.

In Europe, the European Medicines Agency has issued a similar warning for fezolinetant (Veoza), with liver tests required before starting and monthly for the first three months ¹². The European Menopause and Andropause Society (EMAS) says that for healthy women under 60, or within 10 years of menopause, the benefits of appropriately chosen hormone therapy generally outweigh its risks ¹³.

What is still uncertain

The mechanism is better understood than it was, but there is no way to predict at the outset how long your symptoms will run or how severe they will get. The SWAN risk factors describe populations, not individuals ¹.

Why symptom duration varies so much between ethnic groups is unknown ¹.

And there is very little evidence to guide the question women ask most often after a dose change: how long should you wait before deciding it is not working? NICE offers a structural answer rather than a physiological one, recommending review of each treatment at three months to assess effectiveness and tolerability, then annually ⁴.

When to see a clinician

The NHS suggests seeing a GP if you want to discuss options, if symptoms are affecting your daily life, or if you have symptoms such as palpitations ².

NICE allows for a review sooner than the annual one if a treatment is not working or is causing side effects, and recommends referral to a clinician with expertise in menopause if treatments do not improve symptoms or side effects continue ⁴.

Call emergency services if a flush is not a flush

Palpitations and sweating overlap with more serious events. The NHS says to call emergency services for chest pain that feels tight or like squeezing, chest pain spreading to the arms, neck or jaw, severe difficulty breathing, or lips or skin that look pale, blue or grey, and not to drive yourself to hospital ⁹. Not sure of the number: find help numbers where you live.

One practical thing

The threshold SWAN used is easy to borrow. Frequent vasomotor symptoms meant at least six days with symptoms in the previous fortnight ¹. Counting days rather than trying to remember an overall impression gives you something concrete to bring to an appointment, and it gives a dose change something to be measured against.