Why Do I Sweat in My Sleep?

Sweating in your sleep can be from something common, like menopause, drinking alcohol, or just sleeping in a room that’s too warm. However, night sweats can also have more serious causes, like infections and cancer.

This article will go over the possible reasons why you’re sweating in your sleep. You’ll also learn when to see a provider about night sweats and how to cope with them.

Sleep Environment

One of the most common causes of night sweats is sleeping in an environment that’s too hot. It’s normal to sweat in your sleep if your bedroom is warm, you wear heavy pajamas, or you sleep under lots of blankets.

Your body goes through normal temperature changes while you sleep. Most people have a dip in their core body temperature around 4 a.m. During certain phases of sleep, your body temperature may go up, which can lead to sweating.

Anxiety and Nightmares

If you have nightmares or general anxiety, you may have physical effects while you’re sleeping. Sweating can be an anxiety symptom, along with a fast heartbeat, rapid breathing, and shaking.

If you have bad dreams often, especially if you also have post-traumatic stress disorder (PTSD), talk to your provider. Treatment may help stop your night sweats and any other symptoms you have.

Like adults, night terrors can also make kids sweat in their sleep. Night terrors cause a person to abruptly wake up feeling extremely afraid, even panicked. They often occur about two or three hours after falling asleep.

Children who have night terrors may also:

• Thrash around
• Scream
• Act upset or be hard to comfort
• Have a racing heart and fast breathing

If children (especially toddlers) have breathing problems while they’re sleeping, it can make them sweaty and restless. They may even wake up red-faced and drenched in sweat.

Hormones

Hormonal shifts throughout life can also cause sweating at night.

Menstrual Cycle

Some people get night sweats in the pre-period phase of their menstrual cycle as a symptom of PMS, while others experience it mid-cycle around when they ovulate (when their body temperature also increases slightly).

Pregnancy

Hormone shifts that happen during pregnancy can also cause night sweats, and they can hang around after you deliver. Physical changes in your body (like carrying more weight) can also make you feel hotter at night.

Hormonal Disorders

Hormonal disorders (endocrine disorders) can also cause night sweats if hormones that trigger flushing (like serotonin) increase.

One hormonal disorder that can cause night sweats as a symptom is an overactive thyroid (hyperthyroidism). Hyperthyroidism occurs when your body makes too much thyroid hormone.

Night sweats can be a symptom of hyperthyroidism, along with increased appetite, tremors, restlessness, a visibly enlarged thyroid gland (goiter), anxiety, and frequent bowel movements.

Menopause

Perimenopause describes the period of transition after menstruation ends but before menopause is in full swing. People going through menopause may have hot flashes at night that can even wake them up from sleep.

Menopause commonly leads to poor-quality sleep. People going through menopause may have insomnia that’s caused by night sweats and hot flashes.

GERD

It’s less common, but night sweats can also happen if you have gastroesophageal reflux disease (GERD). When you have GERD, stomach acid backs up into your esophagus.

Sweating in your sleep could be related to GERD if you also have other symptoms of the condition, such as:

• Heartburn
• Chest pain
• Vomiting
• Hoarse voice

If your night sweats are caused by GERD, treating the condition may relieve them.

Hyperhidrosis

Hyperhidrosis is a common condition that makes you sweat a lot. You may sweat all day and all night. Some people with the condition just sweat more in a few places on their body, like their hands. Other people sweat excessively all over their bodies.

It’s not clear what causes hyperhidrosis, but it tends to run in families. It can also be caused by a specific health condition (such as cancer or hyperthyroidism) and can also be linked to mental health conditions like anxiety.

Substance Use

Alcohol, marijuana, and other substances may cause sweating, which can happen at night.

Some people notice that they sweat in their sleep after they drink alcohol. Since alcohol widens your blood vessels, it can affect blood circulation and body temperature. You may feel a little "flushed" after having a drink or get quite sweaty, depending on how your body reacts to alcohol. People who drink often or heavily, particularly those who binge drink, might be more likely to have night sweats from alcohol.

For people with sleep disorders like sleep apnea, the muscle-relaxing effects of alcohol can make their symptoms worse. If the muscles in the upper airway are relaxed by alcohol, it can lead to sleep-disordered breathing problems like apnea or snoring—both of which are linked to night sweats.

People who have alcohol or other substance use disorders often have night sweats, especially if they are in withdrawal.

Sleep Apnea

With sleep apnea, your breathing pauses during sleep. These pauses can wake you up or bring you into a lighter stage of sleep. Sleep apnea makes you struggle to breathe, which causes your body to exert itself and may even make you sweat.

Other symptoms of sleep apnea include:

• Feeling very sleepy during the day
• Trouble concentrating
• Waking with a dry mouth, sore throat, or headache
• Loud snoring
• Awakening with a gasp

Sometimes, your bed partner may tell you that you stop breathing periodically when you’re asleep, then snort and gasp.

Night sweats in older people can be related to obstructive sleep apnea. In this condition, you stop breathing multiple times while you’re sleeping. The risk of sleep apnea increases during menopause because of the loss of the hormones estrogen and progesterone.

Sleep apnea can increase the odds that you’ll fall asleep or be inattentive while driving or working. It also increases your risk of heart attack and stroke.

The treatment for sleep apnea is usually a continuous positive airway pressure (CPAP) machine, which can help control your symptoms—including night sweats.

Infections

The symptoms of some serious infections can include night sweats. Here are a few infections that can cause night sweats:

• Tuberculosis
• Brucellosis
• Bacterial infections
• HIV

See your provider if you are sweating in your sleep and have other symptoms of an infection, such as:

• Fever
• Chills
• Body aches
• General weakness
• Fatigue
• Sore throat or cough
• Lack of appetite
• Diarrhea
• Vomiting
• Unintended weight loss

If you’re having night sweats as a symptom of an infectious disease, treating the infection should help. For example, if you have a bacterial infection and are prescribed antibiotics, your night sweats may go away once you’ve finished treatment.

Autoimmune Disorders

When you have an autoimmune disease, your immune system mistakes a normal part of your body for a dangerous pathogen. Some autoimmune conditions can cause excessive sweating, including night sweats. You might sweat in your sleep if you have:

• Graves’ disease
• Sarcoidosis
• Rheumatoid arthritis

Fevers are another common symptom of autoimmune disease, and running a temperature can make you sweaty. Other than fever, autoimmune diseases have a range of symptoms that include:

• Inflammation with redness and heat
• Muscle aches
• Joint pain
• Periods of worsening symptoms alternating with lighter or even no symptoms (flares and remission)

Some Cancers

Some types of cancer, especially Hodgkin’s lymphoma, can cause drenching night sweats. That said, sweating in your sleep is not the only sign of cancer. People also usually have other cancer symptoms, including:

• Persistent, painless lymph node swelling (especially in the neck, underarm, or groin)
• Unexplained fever that does not go away
• Unintended weight loss
• Itching (which can be severe)
• Fatigue
• Shortness of breath, cough, or chest discomfort
• Lymph node pain after drinking alcohol

If you’ve been having night sweats and these other symptoms, make an appointment with your provider.

Medications and Supplements

Many prescription and over-the-counter (OTC) medications can cause night sweats as a side effect. A few examples of common medications that can cause sweating, which can happen at night:

• Antidepressants, such as Effexor XR (venlafaxine), Prozac (fluoxetine), Paxil (paroxetine)
• Immunosuppressive drugs, such as Cellcept (mycophenolate mofetil), Prograf (Tacrolimus), and Arava (Leflunomide)
• Chemotherapy drugs
• Pain medication (both OTC and prescription)
• Steroids
• Cholinergic drugs
• Blood pressure drugs
• Triptans
• Viagra (sildenafil)
• Nutritional supplements like calcium and niacin
• Beta-blockers
• Insulin
• Methadone
• Antibiotics and antivirals
• Accutane (isotretinoin)
• Depo-Provera
• Vasopressin
• Prilosec (omeprazole)
• Sudafed (pseudoephedrine)
• Hormone replacement therapy
• Testosterone

Other Causes of Sweating While Sleeping

If your provider rules out common and serious causes of night sweats, they may consider other conditions. Night sweats are sometimes associated with:

• Diabetes: If you have diabetes, your blood sugar levels can make you sweat more or less than normal. Some people sweat more (and even in their sleep) when their blood sugar levels are too low (hypoglycemia).
• Obesity: Having extra weight puts stress on your body, and the added insulation can make you “run hot,” including while you sleep.
• Hyperparathyroidism: This condition affects your parathyroid gland and makes it pump out too much parathyroid hormone, which makes calcium levels in the body go up. Night sweats aren’t the most common symptom, but they may happen.
• Neurologic disorders: Some diseases that affect your nervous system (including your brain) can cause excessive sweating, which may occur at night. This can include a range of neurological conditions like Parkinson’s disease, autonomic dysreflexia, syringomyelia, pheochromocytoma, or a stroke.

How to Cope With Sweating While Sleeping

If you’re sweating in your sleep, the first step is to figure out if it’s something you can fix on your own. For example, if your room or bedding is too hot, the solution might be to open a window or choose lightweight sheets.

However, if you’ve tried making changes to your sleep environment with no luck, talk to your provider. It’s also important to tell your provider if you’re having other symptoms in addition to night sweats. They can help figure out what’s causing it and recommend the right treatment.

There are a few things you can do to cope with sweating at night and possibly even prevent night sweats:

• Keep your bedroom cool (e.g., running a fan, putting on the AC, cracking a window).
• Use moisture-wicking sleepwear and bedding.
• Wear lighter or no pajamas.
• Drink cold water (you may want to keep a bottle of water or glass of water by your bed to have during the night).
• Maintain a weight that supports your health.
• Don’t drink alcohol.
• Avoid substances, including alcohol and tobacco.
• Avoid caffeine, spicy food, and hot drinks before bed.
• Exercise during the day, but not right before bed.

When to See a Healthcare Provider

Sweating in your sleep once in a while is probably nothing to worry about. However, there are some situations when night sweats warrant a call to your provider, including when the night sweats are:

• Not explained by a previous diagnosis
• Not a side effect of a medication
• Extreme
• Frequent and persistent
• Interfering with sleep
• Affecting your daily life
• Accompanied by other symptoms

Consult with your provider about your symptoms and recommend the next steps. For example, they might want you to have tests that look at what’s happening in your brain and body while you’re asleep, or they may do blood tests to check for infections or markers of diseases.

Summary

Sweating in your sleep is not always a reason to worry. Sometimes, it’s as simple as sleeping in a room that’s too hot or in pajamas that are too cozy. That said, night sweats can also be caused by medical conditions that need treatment.

If you’re sweating in your sleep often or if it’s making your sleep poor, talk to your provider. They can figure out what’s causing your night sweats and make sure the problem is addressed.