10 Surprising Reasons Why You Wake Up Drenched in Sweat But Feel Cold

Waking up in the middle of the night soaked in sweat can be unsettling enough but when your body feels cold and clammy instead of hot, it can be downright confusing. You toss off the covers, shiver, and wonder what’s wrong. Is it the room temperature? Your hormones? Or something deeper going on inside your body?

Let’s explore the science behind this strange experience, why you wake up drenched in sweat yet feel chilled and what your body might be trying to tell you.

Understanding Night Sweats and Cold Sweats

Before looking at the causes, it helps to understand what’s really happening when you wake up sweating.

Night Sweats

Night sweats are episodes of heavy sweating that happen during sleep. They are usually caused by overheating or internal changes in how your body regulates temperature.

Common examples include:

1. Hot flashes caused by menopause or hormonal changes
   
2. Infections or fever
   
3. Certain medications or a warm sleeping environment
   

In most cases, you feel hot before or during the sweating episode.

Cold Sweats

Cold sweats are different, they happen without overheating. You sweat heavily but feel cold, clammy, and sometimes weak.

They can be triggered by:

1. A sudden drop in blood pressure.
   
2. Fear, shock, or stress (the body’s “fight or flight” reaction)
   
3. Illnesses that affect blood flow or oxygen levels.
   

So if you wake up soaked but freezing, you are probably experiencing a cold sweat, not a typical night sweat.

The Physiology: Why Your Body Sweats Yet Feels Cold

Sweating is controlled by your autonomic nervous system, the part of your body that manages temperature, heart rate, and blood flow automatically, without you thinking about it.

Here’s what happens step by step:

1. Your brain’s temperature control center (the hypothalamus) detects stress, a change in temperature, or signs of illness.
   
2. It sends signals to your sweat glands to release moisture, either to cool your body down or to react to a perceived threat.
   
3. In some conditions, especially when blood flow to the skin drops, the sweat evaporates too quickly.
   
4. This rapid evaporation cools your skin excessively, making you feel cold even though your body is sweating.
   

That’s why you might wake up drenched but shivering, your body’s temperature and stress systems are sending mixed messages, causing you to sweat and feel cold at the same time.

Common Causes of Waking Up Sweating Yet Feeling Cold

There are several possible reasons why you might wake up drenched in sweat but feel cold. Let’s look at the main ones, from normal body changes to medical conditions.

1. Hormonal Changes

Your hormones have a strong influence on how your body controls temperature and sweating.

Menopause or Perimenopause
Hot flashes and night sweats are common during menopause. When estrogen levels rise and fall, the part of your brain that controls temperature gets confused. You may sweat heavily during a hot flash, but once it passes, your body cools down too fast and you end up feeling cold and clammy.
A similar thing can happen after childbirth when hormone levels drop suddenly.

Thyroid Problems
Both an overactive and an underactive thyroid can affect body temperature.

• When the thyroid is overactive, metabolism speeds up, which makes you sweat more.
  
• When the thyroid is underactive, metabolism slows down, and your body struggles to stay warm, sometimes causing cold sweats and chills.
  

Low Testosterone or Adrenal Imbalance
In men, low testosterone or problems with the adrenal glands can upset the balance of stress hormones. This can lead to night sweats and sudden cold sensations during sleep.

2. Low Blood Sugar

When blood sugar drops during the night, the body releases stress hormones to bring it back up. This reaction can make you sweat, shiver, and wake up feeling weak or cold.

Other signs include:

1. Morning headaches
   
2. Vivid or strange dreams
   
3. A fast heartbeat
   
4. Confusion or dizziness upon waking
   

This often affects people with diabetes but can also happen if you skip meals or eat irregularly.

3. Infections or Fever Recovery

When your body fights an infection such as the flu or pneumonia, it goes through temperature cycles.

• During a fever, your body heats up and you sweat to release that heat.
  
• Once the fever starts to break, your temperature drops quickly, leaving you shivering and covered in sweat.
  

If you wake up soaked but cold after being sick, it usually means your body has just broken a fever.

4. Anxiety or Stress

Stress and anxiety can continue even while you sleep. Your subconscious can trigger a stress response at night, leading to sweating and a cold feeling.

When this happens:

1. Adrenaline increases.
   
2. Your heart beats faster.
   
3. You start to sweat.
   
4. Blood flow to the skin decreases, making you feel cold.
   

This often causes cold, clammy sweating during nightmares or restless dreams. If it happens often, it may be linked to chronic stress or anxiety.

5. Low Blood Pressure or Poor Circulation

Cold sweats can occur when your blood pressure suddenly drops or when circulation is reduced.

Common triggers include:

1. Dehydration
   
2. Too much alcohol
   
3. Heart problems
   
4. Certain medications
   

When blood flow to the skin decreases, your body reacts by sweating, but your skin feels cold to the touch. This can make you wake up feeling sticky and chilled.

6. Medication Side Effects

Some medicines can interfere with how your body controls temperature or cause cold sweats during sleep.

Common examples include:

1. Antidepressants.
   
2. Diabetes medications, such as insulin or tablets that lower blood sugar.
   
3. Strong painkillers,
   
4. Hormone therapy or steroid treatments.
   
5. Medicines for high blood pressure.
   

If your symptoms started soon after beginning a new medication, speak with your doctor. The dosage or timing may need to be adjusted.

7. Alcohol or Substance Use

Alcohol affects the part of the body that controls temperature, making it harder to stay balanced through the night.

What happens while you sleep:

1. Alcohol widens blood vessels, which increases sweating.
   
2. Later, your blood sugar and body temperature drop, causing chills and cold sweats.
   

You may wake up clammy, shivering, and dehydrated, especially after drinking heavily.
Withdrawal from caffeine, nicotine, or other substances can also lead to night sweats with cold sensations.

8. Sleep Disorders

If you snore loudly or stop breathing for short periods during sleep, you may have a condition called sleep apnea. This happens when breathing repeatedly pauses, causing oxygen levels to drop.

Low oxygen triggers a stress response that leads to:

1. Sudden sweating
   
2. A fast or pounding heartbeat
   
3. Feeling cold when you wake up
   

People with untreated sleep apnea often wake up several times a night feeling sweaty and chilled.

9. Serious Medical Conditions

Although less common, ongoing cold night sweats can be a sign of an underlying illness that needs medical attention.

Infections
Long-term infections such as tuberculosis, human immunodeficiency virus, or heart valve infections can cause repeated night sweats as your immune system stays active.

Cancer
Certain cancers, especially lymphoma and leukemia, may cause drenching night sweats along with chills, tiredness, and weight loss.

Heart Problems
Heart attacks, irregular heart rhythms, or heart failure can all cause cold sweats because of poor circulation and reduced oxygen supply.

Sepsis or Shock
These are medical emergencies where the body goes into crisis mode. Symptoms include sweating, chills, confusion, and cold hands or feet.

If your cold sweats come with chest pain, confusion, shortness of breath, or severe weakness, seek medical help immediately.

Environmental and Lifestyle Triggers

Sometimes, the reason you wake up drenched in sweat but feel cold isn’t medical at all , it comes from your environment or daily habits. Small lifestyle factors can have a big impact on how your body manages temperature during sleep.

1. Room Temperature and Bedding

Your sleep environment plays a major role in how your body maintains comfort through the night. If your bedroom is too warm or your bedding is too thick, you may start sweating as your body tries to cool itself. Once that sweat evaporates, your skin temperature drops, leaving you chilled and uncomfortable.

To keep your sleep space balanced:

• Maintain a cool room temperature between 18°C and 20°C (65°F-68°F).
  
• Keep air circulating with a fan or slightly open window.
  
• Choose breathable, moisture-wicking bedding made from cotton, bamboo, or linen.
  
• Avoid synthetic fabrics that trap heat and moisture.
  

Simple changes like lighter blankets, cooler air, or breathable sheets can dramatically reduce night sweats and post-sweat chills.

2. Eating Late or Spicy Meals

Heavy dinners or spicy foods close to bedtime can raise your body’s metabolism and temperature. Your body works harder to digest food, which increases heat production.

Later in the night, as your body cools down, the combination of sweat evaporation and dropping temperature can make you wake up sweaty yet cold.

To prevent this:

• Finish dinner at least 2-3 hours before bed.
  
• Avoid spicy or high-fat foods late at night.
  
• Choose lighter evening meals like soups, grilled vegetables, or salads.
  

Your body rests better when digestion is calm and temperature stays stable.

3. Dehydration

Even mild dehydration can interfere with your body’s ability to regulate temperature. When you don’t have enough fluids, sweating becomes less efficient and temperature control fluctuates.

You might experience cycles of overheating and sweating, followed by a sudden feeling of cold as your body cools down too quickly.

Helpful tips:

• Drink enough water during the day, especially in hot weather.
  
• Limit caffeine and alcohol in the evening, as both can dehydrate you.
  
• Keep a glass of water near your bed in case you wake up thirsty.
  

Hydration helps your body maintain steady internal temperature and reduces both sweating and chills.

4. Irregular Sleep or Shift Work

Your internal body clock, known as the circadian rhythm, controls hormone release, temperature, and sleep cycles. When your routine is irregular, such as with shift work or frequent late nights, your body’s temperature regulation can go off balance.

This disruption may cause sweating during certain sleep phases and chills at others. The hormones melatonin and cortisol, which regulate sleep and stress, may also fluctuate unpredictably, adding to the problem.

To minimize the effect:

• Try to sleep and wake at the same time daily, even on weekends.
  
• Keep your sleeping area dark, quiet, and cool.
  
• Avoid screens for at least an hour before bed.
  
• Use blackout curtains if you sleep during the day.
  

Restoring a consistent rhythm can significantly improve body temperature control during sleep.

When to Worry and See a Doctor

Occasional cold sweats are usually harmless and often related to heat, stress, or temporary changes in your environment. However, frequent or severe episodes can sometimes point to an underlying medical issue.

It’s important to pay attention to patterns and accompanying symptoms.

Warning Signs That Need Medical Attention

See your doctor if you notice any of the following:

• Night sweats occurring several times per week.
  
• Unexplained weight loss or constant fatigue.
  
• Fever, chest pain, or shortness of breath.
  
• Rapid or irregular heartbeat.
  
• Dizziness or fainting spells.
  
• Side effects after starting a new medication.
  
• Swelling, muscle weakness, or tremors.
  

These symptoms could indicate hormonal imbalances, infections, heart problems, or other medical conditions that require professional evaluation.

What Your Doctor Might Recommend

To find the cause, your healthcare provider may carry out some of these tests:

1. Blood tests: To check thyroid function, blood sugar, or signs of infection.
   
2. Hormone level tests: To identify imbalances such as menopause, low testosterone, or adrenal issues.
   
3. Heart tests (ECG or echocardiogram): To rule out heart rhythm problems or circulatory issues.
   
4. Sleep study: If sleep apnea or breathing interruptions are suspected.
   
5. Imaging tests: Such as chest X-rays or scans if infections or other diseases are suspected.
   

Once the cause is identified, treatment can target the root issue, whether it’s adjusting medication, managing stress, improving sleep hygiene, or treating an underlying health condition.

Waking up drenched in sweat but feeling cold can be unsettling, but it’s often your body’s way of signaling imbalance, in temperature, hormones, or sleep rhythm.
Most causes are simple and fixable through lifestyle adjustments. However, persistent or worsening symptoms should never be ignored.

A cool, calm, and consistent sleep routine, paired with medical guidance when needed can help restore peaceful, sweat-free nights and steady warmth till morning.

How to Stop Waking Up Sweaty and Cold

Fortunately, there are practical ways to manage and prevent these night disturbances.

1. Optimize Your Sleep Environment

• Keep your room cool (18°C ideal)
  
• Use breathable cotton or bamboo sheets
  
• Avoid heavy duvets, layer lighter blankets instead
  
• Use a moisture-wicking mattress protector
  

2. Maintain Regular Sleep and Meal Times

Eat at least 2-3 hours before bed to avoid post-meal metabolism spikes.
Go to bed and wake up at consistent times, it helps regulate body temperature cycles.

3. Limit Alcohol, Caffeine, and Nicotine

All three can trigger cold sweats by disrupting circulation and adrenaline release.
Avoid them within 4-6 hours before bedtime.

4. Manage Stress and Anxiety

Incorporate relaxation habits:

• Deep breathing or meditation before bed
  
• Journaling worries to offload mental stress
  
• Gentle yoga or stretching
  

Calming your nervous system reduces the likelihood of nighttime adrenaline spikes.

5. Balance Blood Sugar

If you suspect low nighttime glucose:

• Have a small protein-rich snack before bed (like nuts or yogurt)
  
• Avoid excess sugar or refined carbs at dinner
  
• Speak to your doctor if diabetic, medication timing may need adjustment
  

6. Review Your Medications

Talk to your healthcare provider if symptoms began after starting or changing a drug.
Never stop medications abruptly, adjustments can usually solve the issue.

7. Address Hormonal Health

For women, tracking menstrual or menopausal patterns can help identify hormonal triggers.
For men, testosterone and cortisol tests may reveal imbalances.

Hormone therapy, supplements, or lifestyle changes may stabilize sweating and temperature control.

8. Support Thermoregulation Naturally

• Stay hydrated (especially in hot climates)
  
• Include magnesium, zinc, and vitamins B in your diet, they support nerve balance
  
• Avoid synthetic sleepwear, choose natural fibers
  

The Psychological Impact: Sleep, Fear, and Body Awareness

Night sweats particularly when cold, can also take a mental toll. You may begin to associate bedtime with discomfort or worry, leading to:

• Difficulty falling back asleep
  
• Fear of serious illness
  
• Restless nights
  

Reassure yourself that most cases are benign and manageable.
Keeping a symptom journal can help identify triggers, patterns often reveal themselves in just a week or two.

When Cold Sweats Signal an Emergency

While most causes are mild, there are moments when you should seek immediate medical attention.

Call emergency services if you experience:

• Chest pain or tightness
  
• Difficulty breathing
  
• Confusion or fainting
  
• Profuse sweating with cold, pale skin
  
• Weak pulse or dizziness
  

These can indicate heart attack, shock, or severe infection, situations where every minute counts.

Summary: Why You Wake Up Sweaty but Cold

Final Thoughts

Waking up drenched in sweat but feeling cold doesn’t necessarily mean something’s wrong, but it’s a signal worth paying attention to.
Your body may be fighting off infection, reacting to hormones, or responding to stress or low blood sugar.

Listen to the clues:

• If it happens rarely, lifestyle tweaks may fix it.
  
• If it’s frequent or accompanied by other symptoms, get checked out.
  

By understanding how your body regulates temperature and what interferes with that balance, you can reclaim peaceful, sweat-free sleep and wake up feeling warm, dry, and refreshed.