

Mary, a 40-year-old high school teacher, was worried. For a week or so, she was experiencing profuse sweating during sleep. This disturbed her sleep and caused inconvenience. When this persisted beyond a week, she went to her doctor for a check-up. She discussed her problem in detail with him. He ordered a battery of tests to include infection or any cardiac problem, but all came negative. He then told her that it was due to hormonal changes in the perimenopause stage.
Night sweats or excessive sweating in the night can be due to multiple causes, most of them harmless. Yet, it causes anxiety in the affected person. At times, if it is persistent or if associated with other symptoms, it can be due to some sinister problem like malignancy.
Hormonal life changes are a common cause for night sweats. During pregnancy, perimenopause, and menopause, night sweats can occur because hormonal changes influence the body’s temperature regulation. Under-activity or over-activity of thyroid hormones, i.e., hypo or hyperthyroidism, can also cause night sweats. Hormonal therapy used for certain types of cancer is known to be associated with night sweats and hot flashes.
Certain other medical conditions, like autoimmune disorders, some cancers, are known to have night sweats as one of the manifestations. Low blood sugar levels (hypoglycemia), have night sweats as one of the manifestations.
Night sweats can occur as a side effect of some medicines, like some antidepressants, some painkillers, and corticosteroids. Tuberculosis is one of the most common infections associated with night sweats. Apart from this, any infection can cause sweating at night, including parasitic, viral, bacterial infections, amoebiasis, etc.
Ischemic heart disease, where blood supply to the heart is affected due to blocks by clots in coronary vessels or due to thickening of walls of coronaries (blood vessels, supplying blood to the heart), has night sweats as one of the manifestations.
Consumption of excess alcohol, caffeine, very spicy foods, vigorous exercise before sleeping, obesity, sleeping in a warm room, thick beddings, are also causes of night sweats. It is known to occur due to anxiety and or stress.
An individual should be aware of the causes of night sweats and try to avoid them through a healthy lifestyle and adequate physical, mental relaxation. Alcohol and tobacco are best avoided. Triggers like tea, coffee should be avoided before bedtime. Wearing loose, comfortable clothes, keeping the bedroom atmosphere clean, cool, and quiet, are measures that help in preventing sweating during sleeping.
If night sweats are frequent, persistent, sweating is profuse, sleep is disturbed due to sweating, if there are associated fever, body aches, anorexia, weight loss, etc., one or more of these symptoms, then it is a signal that one should seek medical advice. Detailed medical history and relevant investigations help pinpoint towards any medical condition that is responsible for the night sweats. Treatment of that condition helps in curing the night sweats.
One should avoid any vigorous physical exercise or activity before bedtime. If one is obese and suffers from night sweats, weight reduction is useful.
Hormone replacement therapy is beneficial in treating night sweats occurring due to hormonal changes. However, while doing it, one should be aware of the potential long-term side effects like increased tendency of blood clotting, resulting in heart attack or stroke, breast cancer, etc.
Those on any medication for diabetes or on diet control for diabetes, should never miss dinner and even take a night cap or some light snack before sleeping to avoid hypoglycaemia and resultant sweating at night.
Dr Rachna Pande is a specialist in internal medicine.