What Are Night Sweats—And What Causes Them?

Ever wake up drenched in sweat, with the sheets and your nightclothes damp to dripping wet? You're likely experiencing night sweats.

Night sweats can be caused by temporary illness, menopause, medical conditions, or stress. It can also be a side effect of certain medications.

If excessive to extreme perspiration while you sleep happens once or twice and then stops with no known cause, you can probably just blow it off. But if it happens more frequently, you may want to talk to a healthcare provider.

Recognizing night sweats is easier than uncovering the underlying cause. Several factors—some benign, others that point to something serious—can leave people experiencing this uncomfortable, sleep-disruptive symptom.

Here's everything you need to know about what night sweats feel like, what causes them, and how to treat them so you can sleep more comfortably.

What Do Night Sweats Feel Like?

Night sweats can feel different from person to person. But generally speaking, they happen in repeated episodes over time (and even on the same night), and they tend to be more severe than simply being in a toasty room.

Night sweats are considered vasomotor symptoms, which are bodily changes that typically come on suddenly but last for only minutes.

"It can feel like a build-up and explosion of heat, a rush of adrenaline, a wave of heat, the list goes on," Colorado-based OB-GYN Sara Lillo, MD, a member of the medical team at digital health platform Nurx, told Health.

On the other hand, some people won't feel them at all—you might even sleep through them. If the sweating doesn't wake you, you may notice uncomfortable dampness when you do wake up, said Dr. Lillo. That dampness can range from mild to drenching, Stephanie S. Trovato, MD, assistant professor of dermatology at The Ohio State University Wexner Medical Center, told Health.

Milder nighttime perspiration is less likely to indicate an underlying disease or infection, Dr. Trovato said. On the other hand, "severe, drenching sweats should raise an alarm for further evaluation," explained Dr. Trovato.

What Causes Night Sweats?

Experts agree: Night sweats can happen for many reasons. Night sweats are a symptom with causes ranging from menopause all the way to cancer, said Dr. Lillo. Here are a few of the more common reasons for night sweats.

Medical Conditions

Medical conditions associated with night sweats include:

• Cancer
• Chronic fatigue syndrome
• Diabetes
• Fever
• Gastroesophageal reflux disease (GERD)
• HIV
• Hyperthyroidism
• Hypoglycemia
• Infections like the flu, COVID-19, or pneumonia
• Leukemia
• Lymphoma
• Malaria
• Mononucleosis
• Obesity
• Obstructive Sleep Apnea
• Rheumatoid arthritis
• Tuberculosis

Mental Health Conditions

Some mental health conditions, including anxiety, depression, stress, and post-traumatic stress disorder (PTSD), can contribute to night sweats.

Night sweats can also be a side effect of a class of antidepressants known as selective serotonin reuptake inhibitors (SSRIs).

Hormones

Menopausal hot flashes are one of the most common causes of night sweats.

"Changing levels of hormones in your body are a very common cause of night sweats," New York City-based family medicine physician Eric Michael Ascher, DO, told Health.

Night sweats and hot flashes can also occur during pregnancy or postpartum.

Endocrine disorders like thyroid disease (hyperthyroidism) and diabetes also affect hormone levels and can be behind night-time sweating.

Certain Medications

"There's a lot of different medications that have side effects of night sweating," pointed out Dr. Ascher.

Types of medications that may cause night sweats include:

• Antidepressants
• Blood pressure medications
• Chemotherapy
• Migraine medications
• Steroids

Even everyday over-the-counter meds like aspirin and Tylenol (acetaminophen) can cause night sweats.

Behavior

Though lifestyle habits aren't always a common cause of night sweats, eating spicy food, drinking a hot beverage or alcoholic drink before bed, or even taking a steamy shower can bring them on, said Dr. Ascher.

Night sweats are also linked to withdrawal from alcohol, nicotine, sedatives, and opioid pain medications.

Idiopathic Hyperhydrosis

"Idiopathic" means that the cause is unknown, so this term covers night sweats that strike even though healthcare providers don't understand why.

"Distinguishing a cause can be tricky," said Dr. Lillo.

Other Risk Factors

Researchers have identified several risk factors for night sweats. Night sweats are more common among people who:

• Are in perimenopause or menopause
  
• Are heavy drinkers
• Are overweight or obese
• Are smokers
  
• Have a history of premenstrual tension 
• Have diabetes
• Were assigned female at birth

When To Talk to a Healthcare Provider About Night Sweats

If your night sweats occur only a few times and then clear up, they may have been caused by a passing infection or lifestyle habit. But if they continue and disrupt your sleep, it's a good idea to check in with a healthcare provider.

To figure out the cause, a healthcare provider will likely inquire about your age and if you've entered menopause, your family medical history, if you have any lifestyle habits that put you at risk factors for cancer or other conditions, and about medications you take.

Share as many details about your night sweats as you can, including their frequency and severity, said Dr. Trovato: "You should mention any medications you may be taking, any other known chronic medical issues, possible infectious exposures, and other associated symptoms."

Dr. Ascher said to make sure you tell a healthcare provider if you are also experiencing any of the following symptoms:

• Extreme fatigue
• Fever
• Swollen lymph nodes
• Unintentional weight loss

A healthcare provider may do a routine exam to see if you have a fever or other symptoms of infectious disease or order further testing. Possible tests may include:

• Chest radiography 
• Complete blood count
• C-reactive protein level
• HIV testing
• Thyroid-stimulating hormone levels
• Tuberculosis testing
  

"A doctor can, and should, address the symptom regardless if the underlying cause is harmful (like cancer) or benign (such as menopause)," added Dr. Lillo.

Treatment Options for Night Sweats

In order to treat night sweats, you'll have to pin down the cause and then respond accordingly. "For example, if a medication is causing excessive sweating that is not tolerable, your physician may consider switching to an alternative medication," said Dr. Trovato.

While you're investigating the cause, there are a few things you can do to ease the discomfort and get a good night's sleep. Dr. Ascher recommended the following to make your sleep environment more comfortable:

• Keep the bedroom cool
• Use layered bedding, so you can easily add or remove layers as needed
• Wear loose-fitting, lightweight, and breathable fabrics at night

Other strategies you can try to prevent night sweats include:

• Get regular exercise, but avoid exercise at bedtime
  
• Hypnosis
• Limit caffeine, nicotine, and alcohol intake
• Manage stress
• Meditation or yoga
• Steer clear of spicy foods
• Talk to a therapist

A Quick Review

Night sweats are a condition related to episodes of sweating while you're asleep. There are different causes of night sweats, like medical conditions or medications; however, there are also risk factors for the condition (e.g., smoking).

Treatment for night sweats will depend on what's causing them. Occasional night sweats are usually nothing to worry about, but if they happen more often, you'll want to see a healthcare provider.