Hot Flushes: What’s Happening in the Body? How Can Acupuncture Help?

Hot Flushes - What's happening in the body? How can acupuncture help?

Hot flushes (or hot flashes) are most commonly associated with menopause, but they are not exclusive to it. They can also occur in people undergoing treatment for cancers such as breast and prostate cancer, as well as in a range of other medical conditions. Regardless of their cause, a hot flush can be debilitating, overwhelming, and can cause embarrassment.

In this post, I'll discuss the mechanisms from both biomedicine and Traditional Chinese Medicine (TCM), along with acupuncture treatment options and advice for managing hot flushes - hopefully providing information for both practitioners and patients seeking effective management strategies.

What Is a Hot Flush?

Medically, a hot flush is described as a sudden episode of intense heat, typically affecting the face, neck, and chest, often accompanied by sweating, skin flushing, palpitations, and/or anxiety/restlessness. These symptoms reflect a rapid activation of the body’s heat-loss mechanisms.

While this description is useful in understanding hot flushes, perhaps more insightful are first-hand description from patients who were kind enough to share what hot flushes are to them:

Patient 1 - Hot flushes due to prostate cancer treatment:

"Hot flushes vary in frequency and intensity from patient to patient but most get them to some degree. I was still working when I started hormone therapy and to suddenly turn beetroot red and break out in floods of sweat for no apparent reason in business meetings was both uncomfortable and embarrassing - often requiring explanation to clients. Worse though were the night time flushes that caused waking several times a night - this on top of the required nocturnal visits to the toilet, another symptom of prostate cancer. As the flush subsides, you can feel suddenly cold and may need to immediately layer up again. Combined, these events gave rise to a very disrupted pattern of sleep with the consequences of that manifesting the next day - tiredness, lack of concentration, irritability. Sharing a bed with a wife / partner causes disruption to their sleep too. Frequent changes of clothes and bedding become commonplace and cause more laundry and ironing. The only slight mitigating factor is that the sweat is 'pre-pubescent' i.e. odourless.

Once you’ve started with flushes you start to look for ways to mitigate them, fans, dietary changes, supplements, wardrobe changes that allow for de-layering whilst out of the home, changes to bed coverings, in severe cases carrying towels - these can all play a part. For me, starting weekly acupuncture brought about the most dramatic change. Within hours of my first session the frequency and intensity of flushes was greatly reduced and that remains the case to this day some twelve years later"

Patient 2 - Menopausal Hot Flushes:

I had my first flush not long after I turned 40 and it just came out of nowhere. It felt like a sudden rush of heat all over my body which disappeared just as quickly. It started happening more and more frequently but was told not to worry by my GP and that it was a normal symptom of the menopause. It was hard to accept it as normal as it was starting to really affect my life everyday. I'd go all blotchy on my face and chest, which was embarrassing, and I'd sweat so much I felt like I needed to get in the shower, which when I could was time consuming, and when I couldn't left me feeling horrible. I stopped wearing make up as it would just melt off, and I felt nervous about going out to do things in case I had a bad flush. I even started taking a change of clothes out with me as some flushes made me wet through. The night time was the worst. I'd wake up drenched, and couldn't bare to be anywhere near my husband in bed, which wasn't nice for him or me. The lack of sleep added to the stress and anxiety of having flushes, which really effected me, although looking back I now know the extra stress and worry may have been another symptom of the menopause.

The TCM Acupuncture Perspective

Hot flushes are interpreted as 'empty heat' in traditional Chinese medicine (TCM). This concept is best explained using the basic theory that underpins all acupuncture theory - the notion of Yin & Yang. For a more comprehensive explanation of how Yin & Yang are used in TCM theory, I'd recommend reading my post on the GB21 acupuncture point, which includes a brief introduction to the TCM theory of Yin & Yang.

For this example, the main thing we need to know is that Yin & Yang represent the balance between two opposing things - they are a mutually consuming duality. In the context of hot flushes, the two opposing things are the function of heating and cooling the body; with equilibrium being a stable core temperature.

In TCM terms, Yang is hot, and Yin is cold; so we would want an equal amount of Yin and Yang to maintain this equilibrium. In basic terms, if we have too much Yang, we overheat and we feel hot, if we have too little Yin, we are not able to cool ourselves, we overheat and will feel hot.

TCM theory defines these two basic processes as 'empty heat' and 'full heat' - empty referring to the deficiency of Yin, and full referring to the excess of Yang. These two different mechanisms represent two different sets of symptoms and related acupuncture points. The symptoms of a hot flush are almost exclusive to those associated with 'empty heat'.

My only issue with this theory is that if Yin & Yang are mutually consumable, then if you're at 60% Yang, then you'd have 40% Yin. You would therefore have an excess of Yang, and a deficiency of Yin - so you should experience symptoms of both full heat and empty heat?

This discrepancy aside, I do find the more basic methods of analysis often yield the best results, and regardless of whether you can define the percentages of an intangible and immeasurable concept, the signs and symptoms associated with hot flushes, overwhelmingly point to Yin deficiency within acupuncture theory.

The Biomedical Mechanism: Thermoregulatory Dysfunction

Hot flushes originate in the hypothalamus, which regulates the body's temperature. When doing its job well, the hypothalamus keeps our core body temperature stable. If we're in a relatively neutral environment, we can regulate our body's temperature using blood flow, rather than extreme reflexes such as sweating and shivering. This is called the "thermoneutral zone". When this zone becomes narrowed, even small increases in core temperature trigger these more exaggerated cooling responses such as vasodilation (widening of blood vessels), sweating and increased heart rate. Essentially, while the core body temperature does tend to be elevated before a flush occurs, the threshold for the more extreme temperature-lowering mechanisms is lower - creating an over-the-top response from our body. This is the mechanism behind hot flushes - but how does our thermoneutral zone become narrowed?

What causes a narrowing of our thermoneutral zone?

Menopause - Oestrogen Withdrawal:

During menopause, declining oestrogen levels disrupt hypothalamic stability, leading to:

• Increased sensitivity to temperature changes

• Dysregulation of Serotonin and Noradrenalin which relate to sleep, mood, emotional stability and pain perception. Noradrenaline in particular also has a role in our heat dissipation response.

• Overactivation of KNDy neurons, which drive the mechanisms related to reproduction and development.

All the changes related to a decline in oestrogen are seen to have a direct relationship to our thermoneutral zone, and therefore hot flushes. However, the National Library of Medicine suggest that oestrogen decline is not the only factor in developing menopausal hot flushes, stating - "estrogen withdrawal is necessary but not sufficient to explain the occurrence of hot flushes" - Essentially, all women with menopausal hot flushes have lowered oestrogen, but not all women with lowered oestrogen have hot flushes - so there are other factors that are causing the flushes.

To keep things simple, we won't go into detail on these extra factors, but if it is of interest to you, then please have a read of the National Health Institute's article at https://pmc.ncbi.nlm.nih.gov/articles/PMC4612529/)

Hot Flushes in Cancer Patients:

Hot flushes are also very common in individuals undergoing treatment for hormone-sensitive cancers, particularly:

Breast Cancer

In breast cancer, treatments often aim to block or reduce oestrogen, triggering hot flushes similar to menopause. While the mechanisms causing the flushes are very much the same as menopause, hot flushes from breast cancer treatment are often more intense and frequent.

Prostate Cancer

In prostate cancer, hot flushes are a well-known side effect of androgen deprivation therapy (ADT). This therapy causes a reduction in testosterone levels which subsequently affects estradiol levels (a type of oestrogen hormone), which then disrupts the function of the hypothalamus.

To explain in a slightly more digestible form, our 'patient 1' from earlier in the post describes that "Hormone therapy works by stopping the production of Testosterone on which the cancer ‘feeds’. However, it also suppresses the production of oestrogen, which is also naturally occurring in men. It is the associated drop in oestrogen levels that produces the menopause like side effects of hormone therapy – not just hot flushes but also propensity for weight gain, mood swings etc."

Up to 70–80% of men undergoing ADT experience hot flushes (https://pmc.ncbi.nlm.nih.gov/articles/PMC3747499/).

Other Medical Conditions Associated with Hot Flushes

Hot flushes can also occur in a variety of non-menopausal conditions:

Endocrine Disorders

• Hyperthyroidism - Increased metabolic rate and heat production can mimic or trigger flushing episodes.

• Pheochromocytoma - Adrenal tumour causing surges of adrenaline, leading to flushing, sweating, and palpitations.

• Carcinoid Syndrome - Caused by serotonin-secreting tumours, leading to intense flushing, often with diarrhoea and wheezing.

  
  

Neurological and Autonomic Causes

• Dysregulation of the autonomic nervous system

• Spinal cord injuries

• Certain neurodegenerative conditions

These can alter thermoregulation and trigger flushing episodes.

Medication-Induced Hot Flushes

Several medications can provoke hot flushes, including:

• Antidepressants (in some cases)

• Opioids

• Calcium channel blockers

• Steroids

  
  

Infections and Chronic Disease

• Tuberculosis

• HIV

• Chronic infections

These may cause night sweats and flushing, sometimes confused with menopausal symptoms.

Mechanisms In Summary:

Regardless of the underlying cause, the final pathway to a hot flush involves:

1. Hypothalamus dysfunction due to hormonal or chemical changes

2. Activation of the sympathetic nervous system

3. Peripheral vasodilation (expanding of blood vessels as a means to expel heat from the body)

4. Sweating and heat dissipation

5. Drop in core temperature (often followed by chills)

Regardless of cause, this mechanism is what causes the body response of a hot flush, which explains why hot flushes feel similar across different conditions.

Treatment of hot flushes

Before I delve into the TCM and acupuncture methods of treatment and management, we'll have a look at some of the other options commonly available to people who suffer with hot flushes.

Medication

As the mechanism is the same regardless of cause, many of the treatments or self-help methods are appropriate for any person suffering from flushes, regardless of the cause. The big caveat here is medication in cancer patients. While the underlying mechanism is the same, the chemical and hormonal balance that has led to the hypothalamic dysfunction can vary depending on the type and specifics of the cancer. This basically means that while one medication may readdress the hormone balance in one patient and alleviate symptoms, it may actually further disrupt the balance and accelerate symptoms in another.

Here are some of the commonly used medications to control hot flushes, which should only be obtained through prescription from a doctor or trained prescriber.

• Hormone Replacement Therapy (HRT) - Replaces the oestrogen and progesterone that the body is lacking, most often prescribed for menopausal hot flushes.

• Fezolinetant - Targets nerve pathways that trigger the hot flushes.

• Antidepressants - Affect levels of serotonin and noradrenaline, which, as previously mentioned, affect our heat dissipation response.

• Clonidine: Originally a blood pressure medication, and for the treatment of ADHD. It can help with hot flushes with its effect of relaxing the nervous system.

• Progestogens - Hormonal steroids that are often used in contraceptive medication and other women's health medications - are effective in reducing hot flushes in prostate cancer patients, but can exacerbate flush symptoms in breast cancer patients.

• Oxybutynin - Commonly used for overactive bladder symptoms, but is also used successfully in treating hot flushes in breast cancer patients by blocking nerve signals that trigger sweating and heat spikes in the body.

Diet & Lifestyle

From both biomedical and TCM acupuncture frameworks, the general advice is to avoid things like caffeine, alcohol and spicy foods. From Western perspective, these things are seen to excite the nervous system, raise your core body temperature, and stimulate blood vessel dilation, whereas the Eastern theory views these things as very Yang in nature, and capable of depleting of Yin. I'd view the two explanations as trying to describe the same thing, but the Eastern perspective uses more metaphorical language (have a read of this post if you want to understand what I mean by this - Qi Unravelling the Mystery)

TCM theory also suggests foods that have a 'Yin nourishing' and cooling effect on the body. These foods include white fish, tofu, watermelon, cucumber, linseed and peppermint. Many of the foods recommended by the ancient traditional Chinese dietary framework are high in phytoestrogens, natural plant compounds that mimic the effects of oestrogen in your body.

Acupuncture points for hot flushes

From a biomedical perspective, we've established that regardless of the root cause, the underlying mechanism of hypothalamic dysfunction is the core issue in hot flushes. The hypothalamus also controls the parasympathetic nervous system - our rest and digest state. Acupuncture helps to correct imbalances between the sympathetic and parasympathetic activities and also modulates adaptive neurotransmission - bringing us away from our stress hormones, and towards our feel-good hormones.

From the Acupuncture TCM perspective, this nervous system regulation helps reduce the feedback loop of the stress of hot flushes feeding in as an aggravating factor - In TCM terms, we call this 'calming the Shen'.

We have also established that metaphorically, oestrogen is Yin in nature and the lack of 'Yin' causes 'Empty Heat'. In treatment terms, increasing the body's Yin will increase the noushing, cooling and moistening functions of the body, in turn preventing Yang functions overacting and causing heat to rise out of control.

Taking these things into account, our general treatment principles would be:

• Tonify Yin

• Clear heat

• Regulate the nervous system/Calm the Shen

• Subdue Yang Rising

With the holistic nature of acupuncture, there is no one-size-fits-all acupuncture point prescription, though there are some general go-to points that tend to be indicated in most cases.

NADA Protocol

Auricular acupuncture

The NADA protocol was developed in the US in the 1970's and uses the auricular microsystem of acupuncture points. It was originally developed for withdrawal symptoms from addiction, however it's action of shifting our nervous system from fight or flight to rest and digest meant it was found to be beneficial for other issues too - hot flushes being one of them.

The protocol uses five acupuncture points on the ear, Shen Men, Sympathetic, Liver, Kidney and Lung. These points relate to the five main organs used in TCM theory, and link to the 5 Elements. The theory being that the regulatory function of acupuncture addresses any imbalance in each corner of our body's function, whether that be an aspect that is over-acting or in excess, or underacting or in deficiency. The shorthand explanation being that it regulates our nervous system.

Liver 2

The Liver organ is associated with controlling aspects of Yang energy, Liver 2 being particular indicated for heat or 'fire'. It is located on the foot, the opposite end of the body to where people typically feel flushes, but the idea is that acupuncture draws the Yang towards the acupuncture point, and away from the head and upper body. Liver 2 falls into the Ying-Spring category of acupuncture points which are indicated for heat in the body and changes in the complexion

Spleen 6

The Yin channels of the lower body - Spleen, Liver and Kidney - all intersect at this acupuncture point. Spleen 6 nourishes Yin and Blood, supports the Kidney, and regulates the lower jiao. The lower jiao is describing the aspect of the torso from the belly button down, and is particularly important in treating hot flushes as it contains the organs and energetic functions that help anchor and regulate our body's systems. For example, the lower jiao contains the kidneys which are seen as the root of Yin and Yang.

Spleen 6 is a commonly use point due to its broad range of indications and symptoms treated, many of which relate to the symptoms of menopause generally.

Open Ren Mai (Lung 7 - Kidney 6)

Lung 7 opens Ren Mai and Kidney 6 is its paired confluent point - the points are usually needled bilaterally. The Ren Mai is strongly associated with Yin and the reproductive system, meaning this combination is useful for menopausal symptoms involving declining Yin and disrupted Yin regulation.

Pericardium 6

This point is aimed more towards the stress and anxiety that can be part of the hypothalamic dis-regulation, or knock on effect of it. It regulates Heart Qi, settles the Shen and harmonises the chest and Stomach. It's particularly useful when the symptoms along side the flushes include palpitations, anxiety, emotional disturbance, nausea or sleep problems. It also connects nicely with the Heart–Kidney relationship.

Large Intestine 4

Another commonly used, multipurpose point. It has a strong effect on regulating Qi and releases constraint. It can help move stagnant Qi so that the Liver is less likely to become constrained and generate heat. For a stronger moving effect it can also be paired with Liver 3 (4 gates combination). However due to the heat factors of the flushes, I tend to favour Liver 2 and omit Liver 3, so not to overwhelm these aspects of treatment.

Kidney 7

An important point for regulating Kidney Yang and fluid metabolism. Traditionally used to regulate sweating - hence it's inclusion here.

Heart 6

Points on the Heart channel are often used to 'calm the Shen' and reduce the symptoms of stress and anxiety. Heart 6 is specifically associated with the Yin aspect of the Heart and so indicated for Empty heat. From the flush perspective it's used specifically to target night sweats.

Yin Tang

Yin Tang doesn't specifically treat the underlying Yin deficiency, but can address the emotional/nervous system components of flushing. It calms the Shen, settles the mind and can reduce stress, agitation and sleep disturbance. It a particular favourite of my patients, and it's a great point to use to help them get into that relaxation mode when having acupuncture.

Du 20

Raises clear Yang and calms the Shen. It seems counterintuitive to raise Yang, but 'clear Yang' is supposed to be pure, cleansing and nourishing - presumably replacing the nasty hot and cloggy Yang in the head (I've never quite got my head around this idea, but it works, so I trust the process). It can be useful when there is restlessness, anxiety, insomnia or for the sensation of heat rising upwards.