Night sweats in men: causes, what to check and when to see a GP

Warm bedding, a warm room or a hot evening can make anyone sweat at night. The NHS separates this from true night sweats, which are drenching, leave night clothes and bedding soaking wet and happen even though the sleeping area is cool. It describes regularly waking with soaking wet sheets as something that should be checked by a GP.

The NHS pages used for this guide do not describe night sweats as a normal part of ageing in men, and they list several causes that can be treated or changed, so it is worth mentioning to a doctor, particularly if it keeps happening.

The NHS gives a short list of the most common reasons for night sweats. For men, some items need translating: menopause symptoms are not relevant for most men, but the other causes apply equally.

Most night sweats have a harmless or treatable cause, but they can occasionally be a symptom of something that needs investigating, which is why the NHS says to see a GP if you also have a very high temperature or feel hot, cold or shivery, a cough or diarrhoea, or are losing weight for no reason.

The NHS lists night sweats among the symptoms of non-Hodgkin lymphoma (alongside a painless lump in the neck, armpit or groin, a high temperature, shortness of breath, itchy skin and sudden unexplained weight loss) and of tuberculosis (alongside a cough lasting more than 3 weeks, tiredness, loss of appetite and weight loss). It stresses that these symptoms are common and have many causes, so having them does not mean you have either condition.

The NHS describes excessive sweating as common, affecting the whole body or only certain areas. It may happen for no obvious reason, because of another condition you may have, or as a side effect of a medicine. It says to see a GP if you are sweating excessively and self-help is not working, it has lasted at least 6 months, it stops you getting on with daily activities, it happens at least once a week, it happens at night, you have a family history of excessive sweating or you are taking medicine for another condition.

For self-care the NHS suggests loose-fitting clothes, moisture-absorbing socks, avoiding tight or synthetic fabrics and avoiding things that can make sweating worse such as alcohol and spicy food. A pharmacist can suggest stronger antiperspirants and other products. A GP may refer you for tests if they think another condition may be causing the sweating, and a dermatologist may suggest tablets, a cream, iontophoresis, botulinum toxin injections (which may not be available on the NHS) or surgery.

Many men wonder whether night sweats mean low testosterone. The NHS page on the so-called male menopause lists symptoms such as depression, loss of sex drive, erectile dysfunction, mood swings, loss of muscle mass, tiredness, difficulty sleeping and poor concentration, and does not list sweating among them. It also explains that the term is unhelpful and misleading, that testosterone levels fall steadily at about 1% a year from around the age of 30 to 40, and that this is unlikely to cause problems in itself.

The NHS says that a testosterone deficiency developing later in life, known as late-onset hypogonadism, can sometimes be responsible for symptoms and that in many cases the symptoms have nothing to do with hormones. It is an uncommon and specific medical condition, diagnosed from symptoms and blood tests that measure testosterone, and replacement may be offered as an injection or gel if a deficiency is confirmed by a specialist. Night sweats alone are therefore not a reliable sign of low testosterone and should be assessed in the wider picture.

The NHS says to see a GP if you have night sweats regularly that wake you or worry you, if you also have a very high temperature or feel hot, cold or shivery, a cough or diarrhoea, or if you have night sweats and are losing weight for no reason. The GP will check whether there are other symptoms, and you will not usually need treatment for night sweats themselves.

It helps to bring a list of the medicines you take, including over-the-counter ones, how much alcohol you drink, how often the sweats occur and any other new symptoms. These details point the doctor towards the most likely causes and the tests, if any, that are needed.

On the NHS the GP is the starting point, and tests or specialist referral follow only if the history and examination suggest a cause. Private GP and endocrinology services may offer blood tests more quickly, but the NHS notes that the cause of night sweats is sometimes unknown. If you have private blood results, share them with your NHS GP so that nothing is repeated unnecessarily.