13 Characteristic Night Sweats Causes

2. Tuberculosis

Tuberculosis is a bacterial infection that often affects your lungs, although it can also involve your spine, kidneys, brain, or lymph nodes. It spreads through the air when someone with active lung tuberculosis coughs, speaks, or sings, allowing you to breathe in the bacteria.

You are more likely to become sick if your immune system is weak due to conditions like diabetes, cancer, HIV, or the use of immune-suppressing medicines. When the infection becomes active, your immune system raises your body temperature as part of its response to the bacteria.

As that fever breaks during sleep, you may sweat heavily, which can cause repeated night sweats that soak your clothes or sheets. You may also notice a cough that lasts three weeks or longer. Some people cough up blood or thick mucus. Chest pain, fatigue, fever, chills, weight loss, and loss of appetite are also common.

3. Abscesses

An abscess is a pocket of pus that forms when your body fights an infection. Bacteria often cause abscesses. Germs can enter through a small cut, blocked sweat gland, or infected hair follicle. Staphylococcal infection bacteria are a common cause, including strains that resist some antibiotics.

When white blood cells gather to attack the germs, the area fills with fluid, dead cells, and bacteria, forming a pocket of pus. Skin abscesses are easier to notice. You may see a red, raised lump that feels warm and painful. The area can swell and may leak pus.

Abscesses deeper in your body are harder to spot. You might feel pain in one area, develop a fever, or sweat heavily at night because your immune system stays active while it fights the infection. Tenderness around the area, ongoing swelling or redness, and a general feeling of being unwell may also occur.

4. Medications

Certain medications can cause night sweats as a side effect. You may notice sweating that soaks your clothes or bedding, even when your room feels cool. Antidepressants are a common cause because they affect brain chemicals that help control temperature. When those signals shift, your body may release extra heat through sweat.

Steroids can also lead to sweating because they change hormone levels and may raise body temperature. Hormone therapies used for breast or prostate conditions may also trigger hot flashes and night sweats because they alter hormone balance. Some people feel warm or flushed, especially at night.

Pain relievers, especially strong prescription types, may affect the part of your brain that regulates heat, which can cause sudden sweating during sleep. Medicines that lower blood sugar can also contribute. If your blood sugar drops too low at night, your body may respond by sweating, and you might also feel shaky, weak, or confused.

5. Medication for Migraines

You may take migraine medication to stop pain or prevent attacks, but some of these drugs can trigger night sweats. Acute treatments stop a migraine after it starts. These include triptans, nonsteroidal anti-inflammatory drugs, and anti-nausea medicines.

Some people report sweating, flushing, or a warm feeling after taking them because these drugs can change how blood vessels widen or narrow. Preventive medicines lower how often migraines occur. These include beta blockers, certain antidepressants, anti-seizure medicines, and calcitonin gene-related peptide receptor antagonists.

Because these drugs act on your nervous system, they can also influence sweating patterns. Changes in brain chemicals, nervous system activity, and blood flow can make you wake up feeling hot and damp. Night sweats may appear soon after you start the medicine or after a dose change.

6. Cancer

Cancer can cause night sweats, though this is not always the first sign. Some cancers affect how your body controls temperature or trigger your immune system, which can lead to heavy sweating at night. Lymphoma is one of the cancers most often linked to drenching night sweats. These sweats may soak your clothes and bedding.

You may also notice swollen lymph nodes, weight loss, or ongoing fatigue. Advanced cancers may also cause excessive sweating, either because of the disease itself or as a result of treatment. Certain cancer treatments can bring on hot flashes and night sweats. These include chemotherapy, radiation therapy, hormone therapy, and surgery that removes the ovaries or testicles.

These treatments can lower hormone levels and push your body into early menopause or a menopause-like state. Other medicines used during cancer care, such as certain antidepressants, strong pain relievers, steroids, and some blood pressure medicines, may also contribute to sweating.

7. HIV/AIDS

HIV/AIDS is caused by a virus that attacks your immune system. HIV spreads through certain body fluids, most often during unprotected vaginal, anal, or oral sex or by sharing needles. You cannot get HIV from hugging, kissing, or sharing food. If you think you were exposed, testing can confirm your status.

Over time, the virus weakens your body’s ability to fight infections. AIDS is the most advanced stage of HIV, when the immune system has severe damage. Some people develop flu-like symptoms 2 to 6 weeks after infection.

You might have a sore throat, rash, muscle aches, and sweating during this early phase. These symptoms happen because your immune system reacts to the virus as it begins to spread in your body. Others may have no symptoms for years. As the infection continues, drenching night sweats can appear at different stages of HIV.

These episodes may soak your clothes or bedding and often happen with fever, chills, or swollen lymph nodes. As HIV progresses, your immune system becomes weaker. This makes you more likely to get infections such as tuberculosis or pneumonia. These infections can also cause ongoing fever and heavy night sweats.

8. Neurologic Issues

Problems that affect your brain, spinal cord, or nerves can change how your body controls temperature and sweating. When nerve signals that regulate automatic body functions become disrupted, your sweat glands may become overactive, even if your room feels cool. Common neurologic causes linked to night sweats include stroke, past brain injury, autonomic neuropathy, spinal cord injury, multiple sclerosis, and Parkinson’s disease.

With autonomic neuropathy, damaged nerves can make it harder for your body to manage heat. You might also notice dizziness when you stand up, changes in bowel or bladder habits, or unusual heart rate patterns. Spinal cord injuries can also trigger heavy sweating below or above the level of the injury. In some cases, your body overreacts to minor triggers, such as a full bladder or skin irritation.

Certain neurologic infections or tumors can also cause night sweats. These often come with other warning signs, such as headaches, weakness, numbness, vision changes, or seizures. If your night sweats occur along with new nerve symptoms, such as trouble walking or speaking, the cause may involve your nervous system rather than hormones or infection.

9. Chronic Hyperhidrosis

Hyperhidrosis causes sweating beyond what your body needs for temperature control. This happens when sweat glands become overactive, so you may sweat even when in the room feels cool or when you are resting. Sweating can affect your whole body or only certain areas. Many people notice it on the palms, soles, underarms, or face.

In some cases, the cause is not clear. This type often starts in childhood or the teen years and may run in families. Night sweats related to hyperhidrosis may soak your sleepwear or sheets. Sometimes, chronic hyperhidrosis develops with another health problem, such as thyroid disease, low blood sugar, infections, nerve problems, or heart conditions.

Certain medicines and alcohol use can also make sweating worse, including at night. Treatment depends on the type and cause. Options may include strong antiperspirants, oral anticholinergic medicines, nerve-targeting treatments, or procedures that reduce sweat gland activity.

10. Hypoglycemia

Hypoglycemia means your blood sugar drops below a healthy level. For many people with diabetes, this means a reading under 70 mg/dL. If you do not have diabetes, it usually means a level under 55 mg/dL. Hypoglycemia often affects people who use insulin or other glucose-lowering medicines for diabetes. It can also happen if you skip meals, eat fewer carbohydrates than usual, exercise more than normal, or drink alcohol without enough food.

In rare cases, liver disease, kidney problems, or hormone disorders can also cause low blood sugar. When this happens, your body quickly releases stress hormones to raise blood sugar again. This can trigger sudden sweating at night, even if your room is cool.

You might wake up feeling damp, weak, or anxious. Some people also have headaches or feel very tired in the morning. Other common symptoms include shaking, a fast heartbeat, dizziness, hunger, confusion, or irritability.

11. Anxiety

Anxiety disorder can trigger night sweats even when your room feels cool. Anxiety does not always come from a clear cause. Daily stress, major life changes, or ongoing worry can all play a role. If you feel anxious most days for several months and struggle to manage your thoughts, this ongoing tension can increase nighttime sweating.

When you feel worried or tense, your body shifts into a stress response. This raises your heart rate and body temperature, which can lead to sweating during sleep. Along with sweating, you may notice other signs such as restless sleep, tight muscles, or a sense of fear that is hard to control.

Some people also wake up feeling shaky or uneasy. Certain medicines used to treat mood or anxiety disorders, such as antidepressant medications, can also raise the chance of night sweats. These drugs affect brain chemicals that help control mood but may also influence body temperature.

12. Autoimmune Disorders

Autoimmune disease develops when your immune system attacks healthy cells by mistake. This ongoing inflammation releases chemicals that can affect your brain’s temperature control, which may lead to repeated night sweats even if your room is cool. You may wake up with damp sleepwear or sheets.

Many autoimmune diseases can trigger this symptom. Examples include systemic lupus erythematosus, rheumatoid arthritis, psoriasis, psoriatic arthritis, and Sjögren syndrome. Each condition affects different parts of your body, but they all involve immune system overactivity. Along with night sweats, you may notice joint pain or swelling, muscle aches or weakness, ongoing fatigue, skin rashes, low-grade fever, or dry eyes and dry mouth.

These symptoms often come and go. You might have periods when symptoms flare and times when they calm down. Night sweats may become more noticeable during active flare periods when inflammation is stronger. Some people also notice that fatigue feels heavier the morning after repeated sweating episodes interrupt sleep.

13. Drug Addiction Withdrawal

Night sweats often occur when you stop or cut back on drugs after long-term use. Your body gets used to the drug over time, so when the drug leaves your system, withdrawal begins. Withdrawal-related night sweats often occur with opioids such as prescription pain relievers or heroin, alcohol, certain sedatives, and stimulants.

Withdrawal can affect sleep, mood, heart rate, and body temperature. As your nervous system becomes overactive, your body struggles to adjust without the drug, which can lead to heavy sweating at night. You may notice soaking sheets even if your room feels cool. Symptoms can begin within hours to a few days after you stop using the substance.

You may feel anxious, restless, or shaky. You might also have chills, nausea, muscle aches, or trouble sleeping. If you wake up with repeated drenching sweats and recently stopped using a substance, withdrawal may be the cause.