Why Do I Sweat in My Sleep?
While sweating a little during the night is nothing to worry about, sweating so much you have to change the sheets is a different story. And it’s not just how uncomfortable that sweaty feeling is, it’s the sleep disruption that comes with it that can impact your life.
“Don’t sweat it” is a pretty common turn of phrase in U.S. vernacular, typically meant to tell people not to worry or stress about something. But what do you say if the whole reason why you’re stressed is because, well, you can’t stop literally sweating in your sleep?
Night sweats, the clinical term for when you sweat through your clothes or sheets while you sleep, can be uncomfortable at best and disruptive to your sleep at worst. It’s a fairly common issue, too: Research shows that up to 41 percent of primary care patients report experiencing night sweats. (It’s most common among adults in their 40s to mid-50s.) Suffice to say, if you’ve ever found yourself frantically asking Dr. Google what the heck is going on, you’re not alone.
What are night sweats?
Sweating at night and night sweats are actually two slightly different things. While there’s no official definition, some experts say that true night sweats are characterized as sweating so much that you need to change your bedding. Other definitions say it’s simply when you’re sweating at night even though your bedroom isn’t particularly warm.
You may sleep through this and only notice in the morning, or you may wake up in the middle of the night to find yourself covered in sweat for no apparent reason.
“Night sweats are a nonspecific symptom that patients commonly experience but rarely discuss with their physicians without prompting,” says Carl Bryce, MD, from Abrazo Family Medicine Residency in Phoenix, Arizona, in the journal American Family Physician.
And while night sweats can be a sign of something more serious, Bryce adds: “Most patients who report persistent night sweats in the primary care setting do not have a serious underlying disorder.”
Even if you don’t experience drenching sweat, waking up sweaty is never a nice feeling. And if it’s waking you up in the night, it’ll easily start impacting your days, so it’s worth finding a fix.
You should speak to a doctor about night sweats if you have symptoms like a fever, cough, or unexplained weight loss, or if you get night sweats regularly.
Why Do I Sweat in My Sleep?
It can be hard to figure out what exactly is causing it, but here are the most common causes of night sweats:
1. Sleep Environment
If your sleep environment is too warm, your body will sweat while you sleep. It may sound obvious, but it’s not always easy to get the temperature right. Everything from your pajamas to your bedding to the weather will affect the temperature of your sleep environment.
Plus, our body temperature fluctuates throughout the night — meaning you may be cool enough at one point and sweating at another.
2. Hyperhidrosis
Hyperhidrosis is another potential cause of night sweats. Hyperhidrosis is the clinical term for excessive (ie: dripping) sweating, and is caused by certain illnesses, medications, or having an underlying genetic condition. In most instances, hyperhidrosis shows up on the hands, feet, face, and under the arms. This condition is diagnosed through lab and/or sweat tests to determine the severity and to identify if there are any other underlying causes for your excessive sweating.
3. Stress and Anxiety
Chronic stress and anxiety can manifest into night sweats. People with post traumatic stress disorder (PTSD) also often experience night sweats and other sleep disturbances. This makes sense considering both stress and anxiety can cause nervousness, which can lead to sweating in waking activities, too. In fact, researchers found that people with hyperhidrosis have anxiety and depression at higher rates compared to the general population.
4. Perimenopause and Menopause
Hormonal changes are the cornerstone of perimenopause, when your ovaries gradually stop making the sex hormone estrogen. When these hormone levels decline, hot flashes and night sweats become much more common.
The specific underlying mechanism as to why a lack of estrogen can trigger hot flashes is not fully understood yet. But experts believe that the changes in estrogen make it harder for your hypothalamus (the part of your brain that controls stuff like body temperature and heart rate) overreact to changes in body temperature. This can trigger hot flashes and sweats (including night sweats) as your body struggles to keep its equilibrium.
5. Medications
Certain medications can have night sweats as a side effect because they can impact your body’s ability to regulate temperature. Antidepressants, hormone therapies, and steroids are the general drug categories most likely to cause night sweats.
There are various reasons why a medication could cause night sweats. For example, selective serotonin reuptake inhibitors (SSRIs), a common type of antidepressant medication, may block a certain kind of receptor in your brain that impacts your heart rate and body temperature, which could trigger excessive sweating. (In fact, an estimated 20 percent of patients on antidepressants deal with excessive sweating.)
6. Infection
Night sweats may be a clear indication of your body’s attempt to fight off an infection. Infections can lead to fevers, which can obviously lend to feeling particularly hot (or developing cold sweats) at night.
Common colds and the flu are known to trigger fevers, chills, and cold sweats. Your night sweats might coincide with other symptoms like fever, muscle aches, and swollen lymph nodes. Infections such as tuberculosis, HIV, and endocarditis [when bacteria makes its way through the bloodstream into the heart valve] are associated with night sweats
7. Alcohol
There’s a good reason why sleep experts pretty universally recommend that people consume less alcohol: it is a notorious sleep disruptor. While alcohol is initially sedating, once it is metabolized it can lead to disrupted, poor quality of sleep later in the night.
Alcohol can also trigger night sweats. The mechanism is a little complicated. But according to American Addiction Centers, alcohol acts as a vasodilator, meaning it widens your vessels. Wider blood vessels let blood travel faster throughout your body, distributing heat and making you flushed. Your liver also creates heat as it works to process the alcohol. This might make you feel warm and trigger sweating.
8. Thyroid problems
An overactive thyroid — the gland that releases hormones to regulate your metabolism and more — can also be to blame for night sweats. Hyperthyroidism (where the thyroid gland produces too much thyroid hormone) can make people very sensitive to heat and is associated with night sweats and excessive sweating in general.
How To Deal with Night Sweats
Since there are so many potential causes of night sweats, it helps to narrow down why you might be experiencing the nocturnal sleep disturbance.
First, try to rule out any lifestyle factors that might be triggering night sweats. Obvious low-hanging fruit includes making sure your room is cool enough for sleeping. Keep the room at a stable temperature between 65 and 75 degrees Fahrenheit, which is the lower end of the spectrum for the most comfortable sleep. (Adults over 65 years old might benefit from higher temps between 70 and 74 degrees Fahrenheit, according to new research.) If you have less control over the indoor temperature in your bedroom, try adding a fan for air circulation and movement instead.
Consider ditching heavy bedding and sleepwear in order to stay cool, too. Look for moisture-wicking material like bamboo, lyocell, and cotton in both your bedding and PJs. (Or if you’re feeling it, sleep nude!)
As for alcohol consumption: You should stop drinking four hours before bed to prevent night sweats. And evaluate how much you’re drinking, too, since women who consume eight or more drinks per week may be more prone to excessive drinking-related health conditions (including stuff like night sweats). If you’re open to a sober curious lifestyle, consider opting for a mocktail before bed instead.
Managing stress and anxiety might also help reduce your risk of night sweats. The specifics depend on what work best for you, but some options may include: changing your bedtime routine to include a relaxing bath or shower infused with essential oils for anxiety; taking a sleep-boosting magnesium supplement or eating foods high in magnesium and other sleep-promoting nutrients; regularly meditating using the Headspace or Calm apps (or other tool of your choice; doing yoga regularly; getting support from a loved one or mental health professional.
If you’re taking antidepressants, oral steroids, or other medications that might be linked to night sweats, talk to your doctor about how to mitigate the side effects — or whether it’s worth trying a different medication. Do not stop taking it without consulting your health-care provider.
When to see a doctor about your night sweats
There are a few tell-tale signs that it’s time to see a doctor for your night sweats: if you’re losing sleep and/or soaking your sheets and clothes on a regular basis, if tackling lifestyle factors like bedroom temperature isn’t helping, and if you know you have an underlying condition that might trigger night sweats, like perimenopause. All of these situations mean that you need a health-care provider’s help and support to understand the underlying cause of your night sweats, as well as more targeted, clinical care.
What night sweat treatment entails depends on your unique health situation. For example, if hormonal changes due to perimenopause are the culprit, your doctor might recommend hormone therapy, which replaces the dwindling estrogen in your body to mitigate some of the worst side effects. (Hormone therapy has been shown to be safe and effective for perimenopausal women under the age of 60 for specific concerns like hot flashes.)
Or if you meet the criteria for sleep apnea, your doctor might send you to a sleep specialist for further testing (like a sleep study to see what your breathing is like at night). From there, treatment typically includes getting fitted for a special device (like a CPAP machine) that keeps your airway open while you’re asleep. With thyroid issues, you might be referred to an endocrinologist for more testing and diagnosis.
The important thing is to try and see your doctor to understand what’s going on and how to get help. Soon, you won’t have to sweat it — literally.
