For some women, hot flushes and night sweats can be debilitating symptoms of perimenopause and menopause
· Hot flushes and night sweats are well-recognised (but not the most common) symptoms
· Numerous treatment options are available but their effectiveness and safety data varies
· HRT is an effective and usually fast treatment for flushes and sweats
Hot flushes, characterised by sudden feelings of warmth across your body, particularly your face, neck and chest, and night sweats are a common symptom of perimenopause and menopause. In fact, for many years they were incorrectly seen as the defining symptom. This has led to some healthcare practitioners potentially overlooking perimenopause and menopause in women who do not experience them.
A Newson Health survey of 5,744 women found 65% had experienced hot flushes and night sweats as a symptom of perimenopause or menopause, making them the 16th and 18th most common symptoms (brain fog, experienced by 90% of women, was the most common symptom) [1].
The physical impact of perimenopause and menopause usually extends beyond vasomotor symptoms – as you have hormone receptors throughout your body on every cell, when levels of oestradiol (oestrogen), progesterone and testosterone fluctuate and fall during perimenopause and menopause, this often triggers a whole host of symptoms. If you experience flushes and night sweats, you’ll likely to have other symptoms too.
Why do flushes and sweats occur?
Body temperature is controlled by an area of your brain called the hypothalamus. It contains KNDy neurons that are linked to how you perceive temperature and how you respond to it. When hormone levels start to fluctuate and then fall, it can cause a disruption in this area, which then leads to hot flushes and night sweats occurring.
Dr Sarah Glynne, GP, menopause specialist and member of Newson Health’s research team explains: ‘Essentially what happens is that your body register a small change in core temperature then there’s an exaggerated response. Your body reacts by trying to cool you down even though actually you’re not that hot. So, you get hot flushes that are caused by vasodilation, which is when the capillaries under the skin dilate, they go red and flushed and lose heat by radiation.’ Sweating works to help you lose heat by evaporation and initiate behaviours that will cool you down, for instance by taking off layers of clothing.
The impact of flushes and sweats
Like with other symptoms of perimenopause and menopause, women’s experiences of flushes and sweats can vary – for some women, these may not be their most severe symptom but for others they can be really debilitating.
Dr Sarah says: ‘Some women, probably up to about half of the women who do get hot flushes and night sweats, get them badly, moderate to severe severity. They have a negative impact on their mood, their sleep, their ability to work.’ Some women report having to take numerous showers throughout the day, while others find regularly “burning up” means they can’t live their lives as they would like.
There is also some evidence that hot flushes and night sweats can affect your future health as some research has shown they are linked with cardiovascular disease, for example [2]. However, the underlying cause for both vasomotor symptoms and cardiovascular disease can be low hormone levels, especially low oestradiol. So it is not that the hot flushes are causing the increased risk of cardiovascular disease; it is the low oestradiol that leads to hot flushes occurring and also the low oestradiol directly affects the cardiovascular system leading to an increased risk of cardiovascular disease [3].
Hot flushes and sweats shouldn’t be dismissed as a minimal symptom or something to “get over”, especially when effective treatment is available.
How can I manage hot flushes and sweats?
HRT
The National Institute for Health and Excellence (NICE) menopause guidance states that the first-line treatment to manage symptoms of perimenopause and menopause is HRT [4]. HRT replaces the hormones – oestradiol, progesterone and sometimes testosterone – that are missing or have declined in your body, which has triggered the sweats and flushes.
Many women are surprised to at how effective HRT is in resolving flushes and sweats – they usually stop within a few weeks of starting HRT (other symptoms, such as low mood, muscle and joint pains and vaginal dryness, can take longer to resolve). If they do not improve, then the dose or type of HRT may need improving or there may be another underlying cause (not related to hormones) of your symptoms.
Herbal supplements
Supplements such as black cohosh, isoflavones such as red clover, and St John’s wort are sometimes taken to relieve symptoms of flushes and sweats.
NICE guidance states that there is some evidence that these three supplements can have an impact on hot flushes and sweats [5]. However, it also states that their quality and strength can be variable, and their safety is uncertain. There may also be interactions with other medications. For instance, NICE guidance warns against taking St John’s wort if you have had or have breast cancer as it can interfere with some drugs, tamoxifen for example, plus medications to prevent blood clots and manage seizures. Cancer Research UK recommends that women with breast cancer, liver problems or high blood pressure don’t take black cohosh as there is a lack of research on the impact it could have [6].
RELATED: Do I need supplements during menopause?
Medications
Fezolinetant works, in the most simplest sense, by blocking the KNDy neurons to dial down your body’s exaggerated response to temperature. The idea is by blocking those neurons, hot flushes and sweats will be prevented.
The drug is not yet available on the NHS but is available from some private clinics. So far, there haven’t been any trial comparing its effectiveness to HRT, nor any trials lasting longer than one year, nor any including women who’ve had breast cancer.
Interestingly, one of the noted side effects of fezolinetant is hot flushes, and in higher doses it’s been shown to suppress testosterone levels. Some perimenopausal or menopausal women already experience low testosterone so fezolinetant could potentially exacerbate side effects of low testosterone.
Some 2.1% of women taking fezolinetant in a clinical trial developed signs of liver damage (elevated levels of liver enzymes) that resolved when the drug was stopped [7]. Another paper reported an increased incidence of cancer in women treated with fezolinetant compared with placebo [8].
It’s also worth bearing in mind that, unlike HRT, fezolinetant won’t treat any other symptoms of perimenopause such as brain fog or muscle joint pain – it purely works on flushes and sweats.
RELATED: Fezolinetant explained
Lifestyle adjustments
If you’re experiencing flushes or sweats, you may be at higher risk of dehydration. This can lead to a surge of adrenaline, the so-called fight-or-flight hormone, which can in turn help to increase the number and intensity of your hot flushes. Drink plenty of water to keep yourself hydrated and ward off spikes of adrenaline.
The evidence on whether alcoholic drinks contribute to hot flushes is mixed, anecdotally many women will say they find alcohol can be a trigger, while a study has found that caffeine intake is linked to vasomotor symptoms [9].
Choose clothing and bedding that are made from lightweight, natural fabric to keep your temperature low.
Finally, don’t be afraid to talk to a healthcare professional about hot flushes and sweats – you don’t need to put up with them and treatment is available.
RELATED: Handling hot flushes and night sweats
