Hot flushes: causes, what helps and when to see a GP

The NHS describes hot flushes as episodes when your face, neck and chest suddenly feel very hot or cold. They can make you sweat a lot, cause palpitations or anxiety, or make you feel dizzy, and last for several minutes. They can happen at any time of day; at night they are called night sweats and can disrupt sleep.

NICE CKS groups hot flushes and night sweats as vasomotor symptoms and lists them with a change in menstrual pattern, mood disorders, urogenital symptoms, altered sexual function and sleep disturbance as features that should make a clinician suspect perimenopause or menopause.

The commonest cause by far, in women aged roughly 45 to 55, is falling oestrogen during perimenopause and menopause. The NHS says menopause usually affects women between 45 and 55 but can happen earlier. Other causes need to be considered, especially if flushes occur outside this age range or with other symptoms.

Hot flushes are not an emergency in themselves. The NHS menopause page lists reasons to contact a GP: wanting to know your options, symptoms such as a fast heartbeat (palpitations), a change in bleeding pattern with heavier rather than lighter bleeding, or any vaginal bleeding after 12 months without a period. It says postmenopausal bleeding is not usually serious but can be a sign of cancer, which may be easier to treat if found early.

Features that go beyond the usual menopause picture are reasons to ask for assessment rather than assume menopause: a fever that does not settle, drenching sweats with unexplained weight loss, a fast or irregular heartbeat, chest pain or breathlessness, a lump, or flushes starting suddenly in a young person. Chest pain with sweating is a different matter and needs 999, as the NHS chest pain advice says.

• Vaginal bleeding after 12 months without a period, however light.

• Heavier periods than before in the perimenopause.

• Palpitations or a fast, irregular heartbeat.

• Flushes starting before 40, which CKS associates with premature ovarian insufficiency.

• Sweats with weight loss, fever or lumps.

• Mood symptoms that feel unmanageable or affect safety.

NICE CKS lists the history: symptoms and their impact on quality of life, lifestyle, contraception, cervical screening status, family history, previous treatments and wishes, current medication and other conditions. The doctor will ask about the menstrual pattern, because irregular cycles are often the first sign. The NHS notes that hormonal contraception can make it harder to tell if you have reached perimenopause or menopause, since it can affect periods.

CKS says blood FSH should not be used to diagnose perimenopause or menopause in otherwise healthy people aged 45 or over with typical symptoms, but may be considered under 40 with suspected premature ovarian insufficiency, at 40 to 45, and over 50 on progestogen-only contraception.

The NHS suggests lightweight clothing, keeping the bedroom cool at night, a cool shower, fan or cold drink, finding ways to reduce stress, avoiding triggers such as spicy food, caffeine, hot drinks, smoking and alcohol, regular exercise and keeping to a healthy weight. It says cognitive behavioural therapy can also help manage hot flushes.

For wellbeing generally it advises plenty of rest, regular sleep routines, a healthy balanced diet, calcium-rich foods, weight-bearing exercise for bones, relaxing activities such as yoga, tai chi or meditation, and talking with others going through the same thing. The NHS says herbal remedies and complementary medicines such as red clover and black cohosh have very little evidence on how well they work or how safe they are, and some may cause serious side effects with other medicines.

The NHS says to talk to a doctor, nurse or pharmacist about HRT and other options. HRT contains oestrogen, with progestogen added to protect the womb if you still have one; the type depends on whether you still have periods or have had a hysterectomy. CKS says HRT should be prescribed at the lowest dose for the shortest possible time, with a regular review of how well it works, adjustment of dose or preparation and advice on stopping, after an informed discussion of benefits, risks and contraindications.

If HRT does not work, is unsuitable or is not wanted, the NHS says other treatments are available: CBT, or if that does not help a doctor may suggest clonidine or an antidepressant. CKS also lists fezolinetant as an option for moderate to severe vasomotor symptoms when HRT is unsuitable. Specialist referral is offered if symptoms continue despite treatment, side effects are troublesome or there is uncertainty about the best option.

The NHS says symptoms usually last for 7 to 9 years, sometimes longer, and that they change: hot flushes and night sweats may improve and be replaced by low mood and anxiety, while joint pain and vaginal dryness can continue after menopause. It is possible to get pregnant during perimenopause: the NHS says contraception is still needed for 1 year after the final period if aged 50 or over and 2 years if aged 40 to 49.