Dr Margaret answers emailers’ embarrassing problems
in this monthly problem page.

Night sweats

Dear Dr Margaret
We have read your article about sweating, but my partner’s problem is different. He does not sweat much in the day, but he wakes in the night drenched in sweat and has to change his T-shirt. Is there a remedy? 

Night sweats are a surprisingly common problem, especially in middle-aged people. There are lots of possible reasons. Your partner needs to discuss it with his doctor, but it is quite likely that no cause will be discovered.

Alcohol seems to be a common cause, so it might be worth seeing whether stopping alcohol altogether would solve his problem. Is he overweight and a snorer? If so, he may have sleep apnoea, which causes restless sleep and, in some cases, night sweats. Some people with restless legs syndrome wake with sweating as well as with the discomfort or jerking of the legs. The doctor will also wish to exclude an overactive thyroid, so will ask about nervousness, palpitations and weight loss. It is also worth checking whether medication might be the cause; aspirin or acetaminophen (paracetamol) are the most common culprits. People taking treatment for diabetes can have night sweats if their blood sugar falls too low in the night, so if your partner is diabetic he should certainly report the sweats to his diabetes doctor. If the sweats are a new problem that has followed a sore throat, he might have glandular fever (infectious mononucleosis), which is a common viral infection that usually clears up in a week or two.

All doctors were taught in medical school that night sweats can be a symptom of tuberculosis. Therefore, when a patient says they have night sweats, doctors always consider tuberculosis, but this is actually a very unusual cause. Other serious causes include HIV infection and lymphoma.

Sources of further information
Mold JW, Mathew MK, Belgore S et al. Prevalence of night sweats in primary care patients: an OKPRN and TAFP-Net collaborative study. Journal of  Family Practice 2002;51:452–6.

Viera AJ, Bond MM, Yates SW. Diagnosing night sweats. American Family Physician 2003;67:1019–24.

Mold JW, Woolley JH, Nagykaldi Z. Associations between night sweats and other sleep disturbances: An OKPRN study. Annals of Family Medicine 2006;4:423–6.