Keep waking up bathed in sweat? We look at common night sweat causes and prevention tips.
Most people wake up feeling hot every once in a while and it’s perfectly normal to sweat occasionally during the night. If the weather is hot or you’re wearing too many clothes in bed, most people will feel a bit hot. But if you keep waking up bathed in sweat or you’re struggling to sleep at all, you might be concerned.
Night sweats are a common symptom of the menopause and some hormonal conditions, but they can also be caused by medications and some medical conditions. The good news is most cases of night sweats aren’t a cause for concern and are easily fixed. Dr Roger Henderson looks at the possible causes of night sweats and how to treat them:
What are night sweats?
The best definition of night sweats is excessive sweating during the night and there are many possible causes for this including simple ones such as sleeping in a bedroom that is too hot or wearing too many clothes in bed.
Feeling warm on your face or body is different to a true night sweat where sweating wakes you up and drenches your clothes and sheets, and are not linked to the bedroom environment.
What causes night sweats?
There are many different possible causes of night sweats. The 10 most common night sweat causes usually seen by doctors include the following:
1. The menopause
Over 80 per cent of women experience severe hot flushes both day and night during the menopause and the perimenopause, and these are triggered by the hormonal changes that occur during this time. Over half of women find they have sweats and flushes before they notice any alteration to their normal menstrual cycle. Night sweats linked to the menopause can be treated with hormone replacement therapy (HRT)
2. Anxiety
Significant worry and anxiety can cause night sweats because of the way our bodies react to stress. Severe anxiety triggers our stress response, the consequences of which include sweating and a raised heart rate. Other common symptoms include nightmares, feelings of worry and dread, digestive problems, unexplained aches and pains, mood changes and feeling tired and generally unwell. Speak with your doctor if you believe you are having symptoms linked to anxiety.
Significant worry and anxiety can cause night sweats because of the way our bodies react to stress.
3. Medication
Taking certain prescription medication can lead to night sweats, particularly the SSRI group of antidepressants – it has been estimated that up to 1 in 5 people taking this type of antidepressant experience excessive sweating at night. Some other drugs used to treat mental health conditions may also trigger night sweats as can painkillers, diabetes medication, steroids and hormonal treatment. Discuss any medication you are taking with your doctor if you feel these may be causing night sweats.
4. Low blood sugar
If you are taking tablets or injecting insulin to treat diabetes, your sugar level may drop during the night causing significant sweating. Low sugar levels (hypoglycaemia) can be dangerous so always discuss this with your doctor or diabetes specialist. These can also occur as a result of drinking an excessive amount of alcohol before going to bed.
5. Infections
The classical infection known to trigger night sweats is tuberculosis (TB) but almost any infection can cause them if it is severe enough, including viral infections such as influenza or Covid-19. Bacterial infections such as abscesses, severe chest infections, heart valve infection (endocarditis), abscesses and bone infections are also well known in triggering night sweats. When an infection is severe enough to cause night sweats, other symptoms such as fatigue, nausea and feeling very unwell are also usually present.
6. Idiopathic hyperhidrosis
This is the term given to excessive sweating by the body both day and night and can be a condition in its own right, where the body produces too much sweat all the time without any identifiable medical cause being found. Specialist treatment can sometimes help with this but usually involves being referred to a specialist.
7. Cancer
Although uncommon, night sweats can occasionally be an early symptom of some cancers, particularly lymphomas and leukaemia. Occasionally, undiagnosed cancers can trigger night sweats along with other symptoms such as weight loss and malaise.
Significant sweating can be experienced in certain hormonal conditions not linked to the menopause.
8. Hormonal disorders
Significant sweating both day and night can be experienced in certain hormonal conditions not linked to the menopause. These include common conditions such as an overactive thyroid gland (hyperthyroidism), and rarer ones such as carcinoid syndrome and pheochromocytomas.
9. Neurological disorders
Although uncommon, disorders affecting the central nervous system can trigger night sweats including following a stroke, autonomic dysreflexia, and conditions causing autonomic neuropathy.
10. Lifestyle factors
Eating hot and spicy food before going to bed, drinking too much alcohol, using recreational drugs such as cocaine, and having too much caffeine in your body are all potential triggers for sweating.
When to see your doctor about night sweats
It is always worth seeking a medical opinion if night sweats become a persistent problem, especially if accompanied by weight loss, fatigue, easy bruising, altered bowel function, pain, a persistent cough or a raised temperature.
The tests your doctor will carry out very much depend on the history of the sweats and the findings of a medical examination. Depending on these, test options include blood tests, X-rays and scans such as ultrasound scans or MRI scans.
Night sweats treatment and prevention
Night sweat treatment depends on the cause, but some causes can be prevented. For many people with mild night sweats, simple measures are often all that are required to treat them effectively. To lower your risk of experiencing night sweats try the following:
✔️ Always make sure your bedroom is a comfortable temperature and not too hot.
✔️ Avoid wearing excessive clothing at night.
✔️ Use lighter duvets, remove heavy blankets and open windows if necessary.
✔️ Practising relaxation techniques at bedtime can be helpful.
✔️ Avoid high intensity exercise close to bedtime.
✔️ Reduce alcohol and caffeine consumption as well as spicy food.
Net Doctor