Causes of Night Sweats

Sweating is a normal response to reasonable levels of exercise, heat and stress, but it can be an issue if you’re sweating excessively during sleep. Night sweats can disrupt your sleep, cause discomfort and be a sign of underlying medical conditions that are causing your body to inadequately regulate its temperature. It can also be a sign that you need to adjust your sleep environment and sleep hygiene.

What Are Night Sweats?

Night sweats are defined as episodes of excessive perspiration during sleep. These episodes can be severe enough to cause you to wake up to your clothes and bedding soaked in sweat.

It’s normal to sweat during physical exertion, when overheated and in other moments of psychological or physiological stress. Before, during and after sleep, your body regulates its temperature according to your circadian rhythm.

While average body temperatures vary, they typically sit around 98.6 degrees Fahrenheit. Your hypothalamus responds to internal and external stimuli to ensure your body generates and maintains heat, producing more heat during the day and lowering your body temperature in the evening and during sleep.

When you’re too hot, the hypothalamus prompts sweat to rise to the surface of your skin from your dermis skin layer, cooling you off. If your body temperature is too high at night and causes you to sweat excessively, it could be a sign that something external or internal isn’t right.

Night Sweats Vs Overheating vs Hot Flashes

Night sweats is a term used specifically to describe excessive sweating during sleep. Hot flashes may occur at any time of day, but they can be called night sweats if they happen during sleep and cause excessive perspiration. Overheating and skin flushing can both be caused by factors, such as warm environments and clothes, but are not considered night sweats unless they also prompt excessive sweating.

Effects of Night Sweats on Health

The primary effect of night sweats on health is regular sleep disruptions. If night sweats occur frequently, it may cause sleep deficiency or sleep deprivation. This can lead to reduced cognitive function on an acute basis and is also associated with long-term health issues, such as diabetes, cardiovascular issues and stroke.

What Causes Night Sweats?

Many factors or conditions can cause night sweats. If you’re experiencing night sweats on a regular or frequent basis and they’re interfering with your sleep and quality of life, it might be related to one of the following conditions.


The onset of menopause and the consequent hormonal changes are usually associated with hot flashes, which affect an estimated 80% of menopausal women. Increased frequency of hot flashes also correlates with higher reports of night sweats.

Women may experience hot flashes from several years to decades. Up to 64% of women report increased sleep disturbances, insomnia and other issues during perimenopause and menopause, and night sweats are a likely factor in increasingly poor sleep.

Hormone Issues

The endocrine system, which includes the hypothalamus, is responsible for controlling hormonal levels in the body. When hormones change or are poorly regulated, temperature regulation may also suffer.

As such, night sweats are linked to hormonal issues, such as hyperthyroidism, adrenal gland tumors and diabetes. Abnormal sex hormone levels may also prompt night sweats, such as during pregnancy or postpartum.

Infection, Illness or Other Medical Conditions

Some infections and illnesses can cause fevers and overheating. If the condition is severe enough, you may also experience night sweats while sleeping. Other medical conditions associated with night sweats include sleep apnea, gastroesophageal reflux disease and HIV. Hyperhidrosis is also a rare condition that causes excessive sweating while the affected individual is either awake or asleep.


Medications or medical treatments are linked to night sweats. Certain radiation therapy and chemotherapy treatments may cause night sweats. SSRI antidepressants and other medications or steroids may also provoke sweating by blocking certain thermoregulating receptors.

Alcohol, drugs and caffeine can have similar effects. These stimulants can cause increased nervous system activity, which may also increase sweating severity at night.

Treating Night Sweats

If you’re experiencing night sweats and sleep disruptions, consider some of these treatments and ways to improve sleep:

  • Reduce stimulant intake: Avoid stimulants, such as alcohol and caffeine, as these can increase body temperature.
  • Keep cool: Keep your bedroom cool by opening windows, turning on a fan or using air conditioning.  Choose sleepwear and bedding that is light, breathable and moisture-wicking. Another alternative to helping maintain your internal temperature is the new break through wearable technology: Embr wrist band
  • Limit stress: Reinforce good sleep patterns and thermoregulation by practicing relaxing bedtime routines.
  • Talk to your doctor about current medications: If you think your medications might be linked to night sweats, talk to your doctor about any adjustments they might advise.
  • Maintain a healthy weight: Obesity is correlated with night sweats and other sleep issues. Lifestyle adjustments or maintenance may help reduce night sweat frequency.

If your night sweats are persistent, even with lifestyle changes, speak to a medical professional. They can look for underlying issues or conditions that may be causing your night sweats and provide appropriate treatment to help you get back to sleeping well and sweat-free.

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