Night sweats (hyperhidrosis) are when you sweat or perspire too much at night, even when your room or bed is cool. There are a number of possible causes.
Key points
- Night sweats are diagnosed when you regularly sweat in the night, even when your room is cool and your blankets light. If you often wake up wet from sweating, see your doctor.
- There are a number of potential causes for night sweats and your doctor will ask questions, examine you and possibly do tests to work out what might be causing them.
- Treatment for night sweats depends on the cause.
- You may be able to reduce night sweats by not getting over-heated at night, avoiding certain foods and drinks, keeping your room cool and exercising regularly.
What are night sweats?
Anyone can get hot and sweat at night if the room is too warm or there are too many blankets on. While this is uncomfortable, it is not thought of as night sweats. Night sweats are when you sweat too much at night, soaking your clothes or bed sheets, even in a cool room.
Cooling yourself and the air temperature down in your room and reducing the number of blankets on your bed might stop the sweats. However, if you continue to sweat despite making these changes, see your doctor.
What causes night sweats?
Night sweats can be caused by conditions such as:
- menopause (hot flushes)
- anxiety
- medications such as antidepressants, thyroid medications, steroids or painkillers
- cancers such as leukemia or lymphoma
- infections such as tuberculosis or pneumonia
- hypoglycemia (low blood sugar).
In some cases, the causes of night sweats are unknown.
How is the cause of night sweats diagnosed?
See your doctor if you are having night sweats. Your doctor will take a thorough history, do a physical exam and may suggest you have some further tests.
What is the treatment for night sweats?
The treatment will depend on what is causing the night sweats.
How can I prevent night sweats?
There are a number of things you can do to prevent night sweats:
- avoid using too many blankets
- make sure your room is cool and ventilated
- avoid eating heavy meals 2 to 3 hours before bed
- have regular daily exercise
- drink enough water
- avoid spicy food, caffeine and alcohol.
Learn more
Night sweats HealthLink, British Columbia
What to know about night sweats Medical News Today
Night sweats Mayo Clinic, US
References
- Night sweats NHS, UK
- Mold JW, Holtzclaw BJ, & McCarthy L. Night sweats – a systematic review of the literature The Journal of the American Board of Family Medicine. 2012; 25(6): 878-893.
Reviewed by
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Dr Sharon Leitch is a general practitioner and Senior Lecturer in the Department of General Practice and Rural Health at the University of Otago. Her area of research is patient safety in primary care and safe medicine use. |