Hot flushes and night sweats

Hot flushes, sometimes called vasomotor symptoms (VMS) or hot flashes, are the most commonly reported menopausal symptom caused by breast cancer treatment.

Hot flushes can be caused by several treatments including:

• Chemotherapy
• Hormone therapy
• Ovarian suppression

How often hot flushes happen can vary for each person, from a couple a day to a few every hour.

They can range from a reddening of the skin or a mild warming of the face, to waves of heat throughout the body.

Some women have a drenching sweat affecting the whole body.

You may also have heart palpitations.

Hot flushes may fade over time and become less severe, but sometimes they can last for many years.

You may get flushes at night, which are known as night sweats. 

These can lead to disturbed sleep and waking in a cold, damp bed and needing to change nightwear and bed linen.

This can be very disruptive, especially if you share a bed.

Disturbed sleep because of hot flushes can mean feeling irritable, having difficulty concentrating and being forgetful.

1. Keep a battery-operated or paper fan with you at all times
2. Wear layers so you can remove clothing when a flush starts
3. Wear loose-fitting clothing made from natural fibres such as cotton or silk
4. Use a silk pillowcase, a specially designed pillow that stays cool or a        cooling scarf
5. Always keep a bottle of water with you
6. Avoid or reduce caffeine, alcohol and spicy foods
7. Carry a water spray to use on your face or wrists to cool you down

Non-hormonal prescription drugs for hot flushes

Several prescription drugs have been shown to relieve hot flushes.

Like any drugs, these can have side effects. You may need to see if the benefits of taking them outweigh these side effects.

Some of these drugs may interact with other drugs you might be taking, so check this with your treatment team, GP or pharmacist.

You may need to try several different drugs before you find one that helps you.

Antidepressants

Studies have shown that some drugs used for depression and anxiety can also help reduce menopausal hot flushes. It usually takes a few days for these to start working.

Antidepressant drugs you may be prescribed include:

• Citalopram
• Escitalopram
• Fluoxetine
• Paroxetine
• Venlafaxine

When used for hot flushes, these drugs are prescribed at lower doses than they would be for depression.

Antidepressants can cause side effects, although for most people these will settle over time.

Possible side effects include:

• Feeling sick (nausea)
• Diarrhoea
• Sleepiness
• Loss of sex drive
• Difficulty having an orgasm
• Dizziness

Antidepressants and hormone therapies

If you’re taking an aromatase inhibitor (letrozole, exemestane or anastrozole), you can take any type of antidepressant.

Some studies suggest fluoxetine and paroxetine may interfere with the way tamoxifen works. If you’re taking tamoxifen, your treatment team may recommend avoiding these drugs.

Anticonvulsants

Gabapentin and pregabalin are drugs usually used to treat chronic pain and epilepsy, but they may also be help reduce hot flushes.

They can have side effects, including:

• Fatigue
• Sleep disturbance
• Anxiety

Taking them at night and slowly increasing the dosage over time may reduce the side effects.

Oxybutynin (anticholinergic drug)

Oxybutynin is a drug usually used to treat an overactive bladder, but it can also help reduce hot flushes.

Side effects can include:

• Dry eyes
• Dry mouth
• Tummy pain

These are usually mild.

Clonidine

Clonidine is a drug often used to treat high blood pressure, but it can also be used to reduce hot flushes. It may be effective for some women but can take a few weeks to work.

Clonidine is used less often to treat hot flushes because of its side effects, which include:

• Light-headedness
• Dry mouth
• Headaches
• Constipation
• Sleep disturbance
• Drowsiness

Neurokinin receptor (NKR) antagonist drugs

These non-hormonal drugs can help manage hot flushes and night sweats by targeting receptors in the brain that control temperature.

Fezolinetant (Vezoah) is approved for use in the NHS. However, it is not approved for use in people who have had breast cancer. There are ongoing trials to see if it can be used for people who have had breast cancer. You can ask your treatment team if fezolinetant is suitable for you.

Elinzanetant (Lynkuet) is not currently available in the NHS. However, trials have shown that elinzanetant is an effective treatment for hot flushes caused by hormone therapy for breast cancer. 

Although the recent studies have shown these drugs to be well tolerated, side effects included headaches, dizziness, fatigue and diarrhoea. 

Hormone replacement therapy (HRT)

If you’re taking HRT when you’re diagnosed with breast cancer, your treatment team will advise you to stop taking it.

Although HRT is an effective treatment for menopausal symptoms, it’s not usually recommended for women who have had a diagnosis of breast cancer. This is because there’s uncertainty about whether HRT increases the risk of breast cancer coming back.

However, your treatment team will discuss whether HRT would be suitable for you if:

• You have severe menopausal symptoms that seriously affect your quality of life 
• Your symptoms haven’t responded to other treatments

They will also discuss the risks and benefits of HRT. This discussion may depend on the features of your breast cancer and your individual situation.

Cognitive behavioural therapy (CBT) for menopausal symptoms

Studies have shown that a type of therapy called cognitive behavioural therapy (CBT) may help manage menopausal symptoms, including hot flushes and night sweats. It can also help with low mood and sleeplessness.

You can talk to your treatment team to find out if there are menopause-specific CBT courses in your local area.

Complementary therapies include a wide range of approaches that some women find helpful in relieving menopausal symptoms and improving their wellbeing.

Compared to conventional drug treatments, there’s much less robust and reliable evidence to show that complementary therapies are effective.

Most complementary therapies are safe for people with breast cancer. However, if you’re considering complementary therapies, speak to your treatment team first.

Your treatment team may advise you to avoid certain complementary therapies if there’s a chance they may interact with your breast cancer treatment.

Complementary therapies include:

• Hypnotherapy
• Acupuncture
• Herbal remedies
• Phytoestrogens
• Aromatherapy
• Homeopathy
• Massage
• Reflexology

There’s no evidence that magnets can reduce menopausal symptoms. If you have, or have had, breast cancer, you should not be offered magnets to reduce your menopausal symptoms.

Find out more information about complementary therapies.

You can visit our confidential online forum and join one of the ongoing discussions about hot flushes.