It’s not uncommon to sweat at night. You may sweat a little or a lot, depending on how many blankets you sleep with, how warm your room is, and even what you ate before going to bed.
But if you sweat enough that you regularly wake up with wet pajamas and bedding, there could be an underlying medical issue.
Night sweats can happen for a number of reasons, and many of them aren’t too serious. In some cases, however, regular episodes of night sweating could indicate a potentially serious medical condition.
Read on to learn more about possible causes of night sweats, tips to relieve night sweats on your own, and when it may be a good idea to see your healthcare professional.
It’s not always possible to determine the cause of night sweats. But other symptoms you experience along with nighttime sweating could help you narrow down an underlying medical cause.
Your room, mattress, and pajamas could all influence whether you sweat during the night. Your bed may be adorned with several cozy blankets that cause overheating. Similarly, your pajamas could be too heavy, or your mattress may not be breathable. Adjusting the environment may help alleviate your night sweats.
Your nighttime routine
External factors beyond your sleeping environment may impact night sweats. These include:
- alcohol use at night
- eating spicy foods at dinner or as a late-night snack
- exercising before sleep
Avoid these behaviors before bedtime to see if your night sweats decrease.
Stress and anxiety
If your night sweats are happening because of anxiety or stress, you might also:
- have feelings of worry, dread, and fear that keep coming back
- find it hard to think about anything besides these feelings
- have sleep issues or unpleasant dreams
- have stomach and digestive trouble
- have unexplained aches, pains, or muscle tension
- feel irritable or have other mood changes
- feel weak, tired, or generally unwell
Addressing the underlying cause of stress and anxiety, generally by working with a therapist, may help improve all of your symptoms.
A range of hormonal issues and hormone disorders can cause excessive nighttime sweating.
Hormonal conditions can cause a range of symptoms, but some general ones include:
- unexplained weight changes
- changes in energy level
- sexual dysfunction
- menstrual changes
Many hormonal issues can be managed.
Medication side effects
Certain drugs can cause night sweats as a side effect. If you’ve recently started a new medication and are experiencing night sweats, talk with the doctor who prescribed your medication.
Some common drugs known to sometimes cause night sweats include:
- steroids, including prednisone and cortisone
- both tricyclic and selective serotonin reuptake inhibitor (SSRI) antidepressants
- pain relief medications, such as aspirin and acetaminophen
- medications for diabetes that help lower blood sugar
- hormone therapy medications
- phenothiazine antipsychotics
If the night sweats have a negative impact on your sleep, a doctor may recommend a different medication or have suggestions to help you manage the side effects.
Hyperhidrosis causes you to sweat excessively to the point of it being noticeable to you and possibly others. It may interfere with your daily life.
But it can be inconvenient and require management. You may have the condition with no underlying causes. Or it may be a symptom of another medical condition or a side effect of medication.
Hypoglycemia occurs when you have low blood sugar. It could cause you to sweat at night or during the day. You may have hypoglycemia if you have type 1 or type 2 diabetes. Other reasons for low blood sugar may include alternations in hormone levels or metabolism.
In addition to excessive sweating during sleep, you may have nightmares or feel disoriented after awakening.
Other symptoms of hypoglycemia are:
- exhaustion or fatigue
- racing or irregular heartbeat
Severe symptoms include losing consciousness or having a seizure.
Gastroesophageal reflux disease (GERD)
You can experience GERD during the day or at night, and it can sometimes cause night sweats.
Along with night sweats, GERD can cause:
- heartburn, often after meals
- chest pain or esophageal spasms
- problems with swallowing
- regurgitation (when liquid or food comes back up after swallowing)
- sleep issues
- respiratory problems, including coughing or increased symptoms of asthma
GERD is generally diagnosed if you experience this at least twice per week, or if more severe reflux happens once per week or more.
Sleep apnea is a condition that causes you to stop breathing while asleep, usually multiple times in a night.
Obstructive sleep apnea generally occurs when something like throat tissue blocks your airway. You can also develop central sleep apnea when certain health conditions affect the function in your central nervous system.
If you have sleep apnea, you might also:
- feel tired during the day
- wake often in the night or sleep restlessly
- wake up struggling to breathe
- have difficulty focusing during the day
- have headaches
Sleep apnea can have serious complications if it goes untreated, such as increased risk for respiratory and cardiovascular issues.
Women going through menopause who experience night sweats may also be at a greater risk for developing sleep apnea, according to a 2018 study.
It’s a good idea to see a doctor for night sweats that happen with other symptoms of sleep apnea.
Some serious infections can also cause night sweats, including:
- tuberculosis, a highly contagious infection that usually affects your lungs
- endocarditis, an infection in the valves of your heart
- osteomyelitis, an infection in your bones
- brucellosis, an infection you can get from animals with brucellosis or unpasteurized products from infected animals
- fungal infections
- infectious mononucleosis (mono)
- other infections
But as with cancer, infections also tend to cause other noticeable symptoms. These include:
- chills and fever
- aching muscles and joints
- body pain
- general weakness or fatigue
- weight loss
- lack of appetite
Call a doctor if you have any of the symptoms above.
In rare cases, night sweats can occur as a symptom of certain neurological issues, including:
Neurological issues can involve many symptoms, but some might include:
- appetite loss or other GI or urinary symptoms
- losing consciousness
- feeling dizzy or lightheaded
- muscular weakness
- numbness and tingling in your arms, hands, legs, and feet
It’s possible for unexplained night sweats to be a symptom of cancer, but this doesn’t happen often. If you do have cancer, you’ll most likely have other noticeable symptoms, too.
These symptoms may seem to resemble other, less serious health issues, like the flu.
It’s a good idea to contact a doctor if you have night sweats and feel fatigued or generally unwell.
It’s particularly recommended to see a doctor if you have a fever that doesn’t go away and you’ve recently lost weight without trying, as these can be early signs of cancer.
Types of cancer often linked to night sweating include:
These cancers also involve the following symptoms:
- persistent fatigue and body weakness
- unintentional weight loss
- swollen lymph nodes
- chest and stomach pain
- bone pain
If you don’t have other symptoms that might indicate something more concerning, try these tips to relieve night sweats:
- Crack a window. Sleep in a cooler room. Leave windows cracked open at night, if possible, or try using a fan.
- Change your bedding. Replace plush or heavy blankets with breathable sheets, light quilts, or even moisture-wicking sheets. It can even help to remove extra bedding and sleep under lighter layers, so you may not need to buy new sheets or blankets.
- Adjust exercise timing. Physical activity just before sleeping could contribute to increased sweating in the night.
- Avoid sweat triggers. Avoid eating spicy foods, smoking cigarettes, or drinking alcohol right before going to bed.
If you only get night sweats occasionally and they don’t significantly affect your sleep quality, you probably don’t need to be too concerned. Still, you may want to mention them the next time you see your doctor.
But if you’re having trouble sleeping, regularly have night sweats, or have other symptoms that concern you, it’s best to check in with a healthcare professional.
Some potentially serious symptoms to watch for include:
- unexplained weight loss
- body aches and pains
- high fever and chills
- chronic or bloody cough
- diarrhea or stomach pain
A doctor can help you get to the bottom of your night sweats and, if needed, come up with a treatment plan.
Your doctor will use several different methods to determine the cause of frequent or disruptive night sweats. These may include:
- discussing your symptoms, health history, and medications
- going through your family history
- conducting a physical exam
- ordering laboratory or imaging tests to determine an underlying health condition
Your doctor may refer you to a specialist if they suspect an underlying health condition that requires specialized treatment.
There are many reasons you may sweat at night.
The first culprit to consider is your environment, including your clothing, bedding, and the temperature of your room. Next, examine your habits before bedtime.
If you adjust these factors and still wake up in sweat, there may be another cause. Speak with a doctor to diagnose and treat the cause so you can get back to more comfortable sleep.