You expect to sweat when you’re exercising or spending time outdoors on a hot summer day. But, waking up in the morning with damp pajamas and sheets can be disconcerting. Although night sweats are troubling, experts say they are also fairly common. In one study, 41% of participants reported night sweats.
What’s behind perspiration while you’re sleeping? “Night sweats can be caused by a wide variety of medical conditions, including infections, medications, hormones, stress, and anxiety,” says Cassie Majestic, MD, emergency medicine physician in Orange, California, founder of drmajestic.com.
What are night sweats?
True night sweats are more than waking up hot when you accidentally leave the thermostat turned up too high. Also known as sleep hyperhidrosis, night sweats occur over the course of several weeks, even when the temperature in your bedroom is cool. It’s not just light perspiration—it’s feeling like your pajamas and sheets are drenched in moisture.
What causes night sweats?
“Sometimes night sweats can be caused because your bedroom is hot or you have too many blankets on your bed,” says Saralyn Mark, MD, an endocrinologist, geriatrician, and women’s health specialist and founder of SolaMed Solutions. “Other times, it can be your body’s way of telling you that something is happening with your health.” Meaning, an underlying medical condition or certain medications could be potential causes of night sweats.
Some common causes of night sweats include:
Up to 85% of women going through perimenopause and menopause experience hot flashes—sudden intense changes in body temperature (mainly bursts of body heat)—and often report their symptoms are worse at night.
“Hot flashes and night sweats occur due to changing hormone levels,” says Dr. Mark. If your doctor finds that night sweats are caused by hormonal changes, ask about hormone therapy, which can often relieve menopause symptoms—namely the hot flashes that cause night sweats.
According to Dr. Majestic, night sweats are a side effect of many common medications including:
- Steroids, such as prednisolone
- Nonsteroidal anti-inflammatory medications (NSAIDs), like acetaminophen, ibuprofen, or naproxen
- Pain relievers (typically prescription narcotics), such as hydrocodone
- Psychiatric medications (such as antipsychotics and antidepressants), including trazodone and bupropion
- Diabetes medications, such as insulin, if you develop low blood sugar during the night
- Hormone-blocking drugs used to treat certain cancers, such as tamoxifen
Check with your healthcare provider or pharmacist if you worry that night sweats could be a side effect of your medication.
Stress and anxiety can also cause night sweats, says Dr. Majestic. “Typically there will be other symptoms such as mood changes, trouble sleeping, extreme sadness or hyperactivity, or constant fatigue,” she says.
If stress or anxiety is the cause of your night sweats, your physician might recommend talk therapy, an antidepressant, or making lifestyle changes.
Night sweats can also be a symptom of hormone disorders, like a thyroid problem, according to Dr. Mark. An overactive thyroid (also known as hyperthyroidism), can cause night sweats, excessive sweating, anxiety, and sleep problems. A simple TSH blood test can determine if a thyroid disease could be causing your symptoms so your physician can prescribe medication to relieve symptoms.
Some people with acid reflux or the more severe gastroesophageal reflux disease (GERD) can experience both nighttime heartburn and excessive sweating.
“People with GERD experience heartburn at least twice a week for several weeks,” Dr. Mark says. “If you have GERD, and it’s not well-controlled, your doctor might recommend taking an H2 blocker such as Pepcid AC or Tagamet HB.”
Certain spicy foods that contain capsaicin trigger the same nerves that make you feel warm, triggering sweating to cool down. Avoiding these too close to bedtime can help.
A night cap might seem like a good way to relax. But, if you’ve been waking up sweaty, it might make sense to switch to a seltzer. Alcohol dilates the blood vessels in the skin, which can lead to sweating.
Any infection that causes a fever can lead to night sweats—whether it’s the flu or a bacterial infection like osteomyelitis. Some people with tuberculosis and HIV may also experience night sweats.
Night sweats can be a symptom of certain cancers, such as non-Hodgkin’s lymphoma or leukemia. Lymphomas usually present with very severe night sweats. Though, Dr. Mark says other symptoms are typically also present such as loss of appetite and unexplained weight loss.
When should I be concerned about night sweats?
The good news, according to Dr. Majestic is that night sweats typically aren’t a symptom of a serious medical condition.
“Night sweats are most concerning when they have been ongoing for two weeks or longer, and are accompanied by other symptoms,” Dr. Majestic says. “Be aware of symptoms such as unintentional weight loss, fevers or chills, body aches and joint pain, or enlarged lymph nodes.
If you notice night sweats accompanied by any of these warning signs, Dr. Majestic recommends speaking with your healthcare provider as soon as possible to screen for certain conditions.
During your appointment, your physician will take a detailed medical history and may also order blood tests and determine the underlying cause.
What lifestyle changes can reduce night sweats?
Pay attention to your evening patterns
Are you eating, drinking alcohol, or exercising late into the evening? Dr. Majestic says each of these things could contribute to your night sweats.
“Also consider what you’re watching on television or reading before you go to bed,” Dr. Majestic says. “Is it anxiety provoking or scary? It may be a good idea to alter those behaviors. If you’re struggling with depression or anxiety, seek the help of a therapist.” Try to remove potential triggers from the hours leading up to bedtime.
Practice good sleep hygiene
Dr. Mark notes that sleeping with a fan can keep your bedroom temperature comfortable and also provide white noise.
“If you experience night sweats, try to keep your bedroom cool, wear light clothing and use lighter blankets,” she says.
Maintain a healthy weight
Carrying extra pounds can cause night sweats and also be a risk factor for developing obstructive sleep apnea, where the throat narrows, restricting your breathing.
If you find that you have night sweats and wake up tired, ask your doctor for a sleep test to determine if you have a sleep disorder, like sleep apnea. Losing weight can help reduce night sweats and also your risk of developing sleep apnea.
“I encourage people with persistent night sweats to make an appointment with their doctor,” says Dr. Mark. “Keep a log of what’s going on in your life and what you eat or drink before bedtime. Your doctor can work with you on treatment to help you sleep comfortably through the night.”