DEAR DOCTOR,

I am 36 years old and lately, I have been experiencing repeated night sweats. At some point, it gets cold but I continue to wet the pillow with sweat. I do not feel sick or anything so what is causing this?

EMMA

DEAR EMMA, 

There is nothing much to worry about regarding night sweats. Sweating while asleep is only the manifestation of overactive sympathetic system during the night. It can simply be due to physical or mental stress.  This can be avoided by learning to relax.

Overeating in the evening, eating late in the evening or eating very hot and or spicy food, inadequate emptying of bowel, are factors that can put a load on the digestive system causing dyspepsia. Apart from nausea or sense of bloating of stomach, there may be sweating when sleeping. In mild cases, this may be the only manifestation. Caffeinated products like tea, coffee, stimulate the adrenergic system. Hence, drinking tea or coffee late in evening can cause night sweats in some people. One should take high fibre food and drink more water. Also taking late evening meals, taking food late in the evening, and taking very spicy food should be avoided.

Presence of infection is yet another cause for sweating during the night. But any infection, whether bacterial, viral or protozoal, would be associated with other symptoms like fever, body ache, and et cetera. It can be diagnosed by a simple blood test and is curable by suitable antibiotics.

Night sweats can be due to hormonal changes in life. 36 years is perimenopausal age. The changes in balance of hormones already starts around this time and actual menopause follows later, few years onwards.

Low blood sugar in the night can cause sweating. Diabetic patients are more vulnerable to low blood sugar in the night, particularly if they have taken insulin or medicines to lower blood sugar. A normal person may have very low sugar and resultant sweating, if he or she has skipped meal entire evening. Even high blood sugar can trigger sweating in the night. Some anti-depressant drugs, medicines used to cure nasal congestion, some anti-cancer drugs, are known to cause night sweats as an adverse effect.

CAD (Coronary artery disease), where one or more blood vessels of heart are blocked, is a sinister cause for night sweats. One affected may have no other symptom except sweating in night. People with obesity, hypertension and or diabetes, high blood lipids, are more vulnerable to develop CAD. There may be other symptoms like chest pain and or breathlessness on exertion, palpitations. But one with diabetes can have attack of CAD without any other symptoms. It is easy to diagnose CAD with relevant tests like electrocardiogram. CAD is curable and the drugs are easily available and even affordable.

Alcohol should be avoided, as it is an independent risk factor for CAD.

Dr. Rachna Pande is a specialist in internal medicine.

rachna212002@yahoo.co.uk