Hot flushes and sweats
This page tells you about hot flushes and sweats caused by a lowering of the amount of sex hormones in your body. Both men and women can have hot flushes because of cancer or cancer treatment. There is information about
Hot flushes can be very troublesome. They are one of the most common symptoms women have when they go through the menopause. About 3 out of 4 women going through the menopause (75%) will have hot flushes. But hot flushes can also happen in women and men because of treatment for cancer. They can be very disruptive, affecting your day-to-day living and making it difficult to sleep. As a result, hot flushes can have a big impact on your quality of life.
Hot flushes are a sudden, spontaneous feeling of warmth which begins in the face and chest and then spreads in waves to the rest of the body. Flushes can happen at any time during the day or night. Their severity varies from person to person.
Hot flushes are often a combination of symptoms including
- Reddening of the skin
- Sweating, which can be light or heavy
- Racing heart (palpitations)
- Feeling anxious, irritable or panicked
Hot flushes can last between 2 to 30 minutes. Some people have a few each month, while others have them every hour. But for most people it is somewhere in between. The flushes usually carry on for a few months but for some people they can last for years.
Hot flushes and sweats in women
Women having a natural menopause usually find hot flushes become less frequent and less severe during the 5 years after their last period.
We know from research that around 7 out of 10 women (70%) who’ve had breast cancer treatment have hot flushes. They are likely to happen more often and be more severe compared to women having a natural menopause. This happens because breast cancer treatments can lower sex hormone production.
Research suggests that if you had hot flushes during your menopause you are more likely to have hot flushes as a side effect when you take tamoxifen as a breast cancer treatment. Tamoxifen is a hormone therapy. The number of hot flushes you have and their severity is about the same with tamoxifen as when compared with women going through a natural menopause.
If you are close to the age that you would naturally start the menopause when you have chemotherapy, you are more likely to go into the menopause and have more severe symptoms.
Hot flushes and sweats in men
Men having treatment for prostate cancer may also have hot flushes. Some men can have them for years. Hormone treatment causes hot flushes in men by lowering the amount of testosterone in the body. We know from research that more than 7 out of 10 men (70%) who have drugs called luteinising hormone releasing hormone (LHRH) blockers will have hot flushes.
Some men have their testicles removed as a treatment for prostate cancer. This treatment is not used very often these days. About half the men who have this treatment (orchidectomy) have hot flushes.
For many people, hot flushes gradually get better over several months. For some people the flushes last as long as they are having treatment, although they do tend to happen less often over time.
In the past, doctors thought that hot flushes were caused only by lowering levels of oestrogen in women and testosterone in men. Researchers now suggest that this is part of the process but it may be more complicated than they first thought. They are looking into a number of possible causes.
One example is that the part of the brain called the hypothalamus controls the production of many hormones. This part of the brain also controls our body temperature. It may be that the chemical messengers (neurotransmitters) the hypothalamus produces cause the hot flushes. We need more research to find exactly what causes flushes so that we can develop treatments.
Hot flushes can be difficult to live with. But here are some suggestions that may help. Some may help to reduce the number of hot flushes and make them milder. Others just help you to cope with them.
- Cut out coffee, tea and nicotine
- Keep your room cool – use a fan if necessary
- Spray your face with a cool water atomiser
- Wear layers of light clothing so you can easily take clothes off if you overheat
- Have layers of bedclothes to remove as you need to
- Wear natural fibres such as silk or cotton instead of man made fabrics
- Cut down on alcohol
- Sip cold or iced drinks
- Have a lukewarm shower or bath instead of a hot one
- Put a towel on your bed if you sweat a lot at night
If you are taking tamoxifen, try taking half your dose in the morning and half in the evening. Lowering the dose can sometimes help too. Always talk to your doctor before altering the dose of any prescription medicine.
If you are finding it difficult to manage your hot flushes, do talk to your doctor or specialist nurse. There are medicines that may help.
The only way to completely stop hormonal symptoms is to take hormones to replace the ones your body is no longer producing. But if you are having treatment that stops you producing hormones, you can’t have hormone replacement therapy (HRT). Doctors recommend that you don’t take HRT if you have had a hormone dependent cancer such as breast or prostate cancer. Even if you have finished treatment they are concerned that HRT may increase the risk of the cancer coming back.
There a number of different medicines that your doctor may prescribe to help to reduce and control hot flushes. But before taking any of these, there is something important to bear in mind.
When researchers want to find out how well a treatment works in a trial, they sometimes test it against a dummy treatment, or placebo. The people taking part in the trial don’t know whether they are taking the new treatment or the placebo. Many of us feel better when taking something that we think will help.
In nearly all trials looking at treatment for hot flushes, people taking the placebo said that their flushes were reduced by about a fifth (20%). It is important to bear this in mind when we are looking at other treatments. If a treatment reduces hot flushes by 20% or less, it may not be better than a placebo. You can read more about the placebo effect in our trials and research section.
Treatments your doctor may suggest include
- Vitamin E
- Hormone replacement therapy
- Cyproterone acetate
A trial of 120 women with a history of breast cancer compared vitamin E with a placebo. They found that vitamin E reduced the number of flushes by one a day. The researchers asked the women which they preferred, vitamin E or placebo. They did not prefer the vitamin E over the placebo. There were very few side effects of vitamin E, so the researchers suggest it is worth trying as a first treatment.
We need more research to find out how well vitamin E really works and more about side effects.
Researchers have found that some anti depressants can help to reduce the number and severity of hot flushes. Anti depressants include fluoxetine (Prozac), venlafaxine and paroxetine (Seroxat).
Anti depressants can reduce hot flushes by just over half in women who have had breast cancer. But doctors don’t recommend some types of anti depressant for women taking tamoxifen. Some types can interfere with how well tamoxifen works. This includes paroxetine and fluoxetine.
For men with prostate cancer, researchers have recently found that venlafaxine can reduce hot flushes by about half. A small trial looking at paroxetine found it can reduce hot flushes by about a third.
Remember that all drugs have some side effects. Anti depressants can cause a dry mouth, headaches, feeling sick and loss of appetite.
Doctors usually prescribe gabapentin to control fits (seizures) but it can also help to reduce hot flushes. In trials for women with breast cancer, it reduced their hot flushes by about half (50%). It also helped with reducing the severity of hot flushes and how long they lasted. Pregabalin is very similar to gabapentin and this may also reduce hot flushes.
There is less information about how well gabapentin works for hot flushes in men. Trials have shown that it does reduce the number but not as much as in women.
Side effects of gabapentin include dizziness and drowsiness. Some women also develop a rash and fluid retention. We need more research to confirm how well these drugs work and find out more about side effects.
Clonidine is a drug used for a variety of conditions, including high blood pressure. It can reduce the number of hot flushes women have but it doesn’t reduce their severity or how long they last. Unfortunately, we know from research that clonidine does not reduce hot flushes in men.
You can have clonidine as a tablet or wear a patch on your skin. Side effects include dizziness, a dry mouth, constipation, drowsiness and difficulty sleeping.
Progestagens such as megestrol acetate (Megace) are hormones. Doctors only consider prescribing progestagens to women and men who have had a hormone dependent cancer if they have severe hot flushes and no other treatment is working. There is no long term research to show whether they are safe to take for people who have had hormone sensitive breast or prostate cancer.
Progestagens can reduce hot flushes by over 80% and seem to work equally well in women and men. Side effects include skin rashes, fluid retention, dizziness, a dry mouth and headaches. They can also cause vaginal discharge and vaginal bleeding (withdrawal bleeding) in women.
Hormone replacement therapy
HRT contains oestrogen. It stops hot flushes in 9 out of 10 women in the general population (90%). In women who have had breast cancer, we know from research that it increases the risk of their cancer coming back. So doctors don’t recommend HRT for women who have had breast cancer.
In men who have had prostate cancer, a man made oestrogen called diethylstilbestrol can stop hot flushes in nearly 9 out of 10 men (90%). Side effects include breast swelling (gynaecomastia) and breast tenderness. There is also a risk of blood clots and heart problems which can be serious. And so doctors do not suggest it very often.
Cyproterone acetate reduces the amount of testosterone the adrenal glands make in men. It can also help to reduce hot flushes. A recent French trial compared it with medroxyprogesterone and venflaxine. They found that all the drugs reduced hot flushes in men. But cyproterone and medroxyprogesterone reduced the number of hot flushes more than venflaxine.
As cyproterone is a treatment for prostate cancer it may interfere with other treatments you are having and so it is not suitable for all men.
Cognitive describes the mental process that we use to remember, reason, understand, solve problems and make judgements. Behaviour describes our actions or reactions to something. Cognitive behavioural therapy (CBT) aims to help us change how we respond to certain situations or emotions. It helps us understand how our thought patterns may affect our feelings or the way our body works. The therapy teaches us how to calm our body and mind. This helps us to control our feelings, think more clearly and generally have a more positive outlook. It can also have physical effects.
Researchers have tried CBT to see if it can help women who have hot flushes and sweats. One Cancer Research UK funded study found that group CBT can reduce the effect of hot flushes and night sweats for women who have had breast cancer treatment. The reductions in sweats and flushes continued after the treatment ended and helped women to feel better, sleep better and have a better quality of life. You can read about this study (the MENOS1 study) on the clinical trials database. You can ask your doctor or breast care nurse whether CBT is available in your area.
There are a number of complementary therapies researchers have been looking at as treatments for hot flushes in general. There is some information about using them after breast cancer but less for men who have prostate cancer. There is information below on
Acupuncture has been researched as a treatment for hot flushes in both women and men. A small study compared acupuncture with the anti depressant venlafaxine. The treatments worked equally well at reducing hot flushes in women with breast cancer. This was only a small study and we need further research to confirm how well both treatments work.
Soy has been tried for hot flushes because women in Asia have fewer hot flushes than women in western countries. People in Asia tend to eat more soy than people in the West. There are mixed results from research, with some trials showing that it reduced hot flushes and others not. There is also some concern about the safety of soy for women with hormone dependent cancers because soy contains plant oestrogens. At the moment there is not enough evidence to suggest that women who have had breast cancer should take it.
Black cohosh is a native plant of North America. In Germany it has been used to treat menopausal symptoms. It is thought to have oestrogen like effects on the body. Evidence from research is mixed. Some trials found that it helped to reduce hot flushes in women and others did not. But an overview of all the trial results found that it did not reduce hot flushes in women. It has not been tested in men.
Red clover is a plant that contains plant oestrogens. Some trials have found that it reduces hot flushes but others have not. There is also some concern that it could increase the risk of cancer coming back in people with hormone dependent cancers because it contains oestrogens.
There are other complementary therapies you may hear about but there is no evidence to show that they work. These include
- Angelica sinensis (Dong quai)
- Evening primrose oil
It is not easy to cope with hot flushes and sweats. Understanding more about them and what you can do to help is a good starting point. If they are interfering with your sleep, try to rest during the day if you can. Tiredness can make it more difficult to cope.
Talk to your doctor or nurse if you are having problems so they can suggest treatments that you can try. You can also contact our cancer information nurses. They would be happy to help.
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