What Conditions Could Cause Night Sweats? An In-depth Look at Potential Health Issues

October 1, 2025 •

4 min read

According to the American Academy of Family Physicians, night sweats are a common experience, with a prevalence ranging from 10% to 41% among primary care patients. This article explores what conditions could cause night sweats, helping to differentiate between environmental factors and more serious underlying health issues.

Quick Summary

This article details the medical conditions, hormonal changes, and lifestyle factors that can trigger night sweats, and when to seek professional medical advice.

Key Points

Identify True Night Sweats: Drenching, severe sweating that is unrelated to an overheated sleep environment is medically defined as true night sweats.
Hormonal Shifts Are Common: Menopause, perimenopause, hyperthyroidism, and hypoglycemia are frequent hormonal causes of night sweats.
Check Medications: Antidepressants, hormone therapy, and other drugs can have night sweats as a common side effect.
Underlying Infections: Conditions like tuberculosis, HIV, and endocarditis can trigger night sweats as part of the body's immune response.
Consider Cancers: While rare, certain cancers like lymphoma and leukemia may cause night sweats, often accompanied by other symptoms like unexplained weight loss.
See a Doctor for Persistent Symptoms: Regular or severe night sweats, especially with other concerning symptoms like fever or weight loss, warrant a medical evaluation.

Understanding True Night Sweats

It's important to distinguish between simple overheating due to a warm room or excessive bedding and true night sweats, also known as sleep hyperhidrosis. True night sweats are severe, excessive sweating episodes during sleep that are unrelated to your sleep environment and can soak through sleepwear and sheets. While occasional instances are usually not concerning, frequent or intense episodes may indicate an underlying medical condition.

Hormonal Changes and Endocrine Disorders

Hormonal fluctuations are a frequent cause of night sweats, especially in women, by affecting the body's temperature regulation.

Menopause and Perimenopause: Fluctuating estrogen levels during these periods are a very common cause, similar to daytime hot flashes. The hypothalamus, which controls body temperature, becomes more sensitive, triggering sweating.
Hyperthyroidism: An overactive thyroid leads to excess thyroid hormone, accelerating metabolism and increasing sweating. Other symptoms can include anxiety, weight loss, and a rapid heart rate.
Hypoglycemia: Low blood sugar can cause sweating. People with diabetes, particularly those using insulin or certain oral medications, might experience night sweats due to nighttime blood sugar drops.

Infections

Several infectious diseases can cause night sweats as the body combats the infection.

Tuberculosis (TB): This bacterial infection, often affecting the lungs, is historically linked to night sweats.
HIV/AIDS: Chronic infections like HIV can be a cause.
Bacterial Infections: Certain bacterial infections such as endocarditis, osteomyelitis, and various abscesses can trigger night sweats.

Malignancies

While not the most common cause, night sweats can be a symptom of certain cancers, often alongside other signs.

Lymphoma: Both Hodgkin's and non-Hodgkin's lymphoma are often associated with night sweats, along with unexplained weight loss and fever.
Leukemia: Some types of leukemia can also cause night sweats.
Carcinoid Tumors: These rare tumors can produce hormones that lead to night sweats and flushing.

Medications and Substance Use

Many medications and substances list night sweats as a potential side effect.

Antidepressants: Various antidepressants, including SSRIs and tricyclics, can cause night sweats.
Hormone Therapy Drugs: Medications used in some cancer treatments involving hormonal changes can induce night sweats.
Other Medications: Steroids, aspirin, and pain relievers may also contribute.
Alcohol and Drug Use: Heavy alcohol consumption can increase body temperature and heart rate, leading to night sweats. Withdrawal from substances can also cause this symptom.

Sleep and Neurological Disorders

Issues with sleep cycles and the nervous system can also manifest as night sweats.

Obstructive Sleep Apnea (OSA): Untreated OSA, characterized by interrupted breathing during sleep, is linked to night sweats that can improve with treatment.
Idiopathic Hyperhidrosis: This condition involves excessive sweating without a clear medical cause. When it occurs during sleep, it's called sleep hyperhidrosis.
Neurological Conditions: Less commonly, disorders like stroke and autonomic neuropathy can impact sweat glands.

Comparing Causes of Night Sweats

To help understand potential causes, the table below compares different categories, their typical symptoms, and recommended steps.


Cause Category	Example Conditions	Other Common Symptoms	Potential Action
Hormonal	Menopause, Hyperthyroidism, Hypoglycemia	Hot flashes, anxiety, weight changes, rapid heart rate, low blood sugar episodes	Consult a doctor for hormonal or metabolic testing.
Infectious	Tuberculosis, HIV/AIDS, Endocarditis	Fever, unexplained weight loss, chronic cough, fatigue	Seek medical evaluation for infections, especially if other symptoms are present.
Malignancy	Lymphoma, Leukemia	Unexplained fever, weight loss, swollen lymph nodes	Prompt medical consultation is necessary for diagnostic tests.
Medication/Substance	Antidepressants, Hormone Therapy, Alcohol	Dry mouth, blurry vision, mood changes, withdrawal symptoms	Talk to your doctor about medication side effects or adjusting dosages.
Other Factors	Sleep Apnea, Hyperhidrosis, Anxiety	Snoring, interrupted sleep, daytime fatigue, excessive daytime sweating	Address underlying conditions; lifestyle and environmental changes can help.

When to See a Doctor

Occasional night sweats due to environmental factors are usually not a concern. However, persistent or severe night sweats warrant evaluation by a healthcare provider. Consult a doctor if:

Night sweats are regular and severe enough to disturb sleep.
They are accompanied by other symptoms like fever, unexplained weight loss, or pain.
You experience a sudden, unprompted increase in sweating.
The sweating causes significant distress or impacts your daily life.

Lifestyle Adjustments for Night Sweats

While medical issues require professional care, some lifestyle changes can help manage night sweats:

Cool Environment: Keep your bedroom cool with fans or air conditioning.
Breathable Fabrics: Wear loose, lightweight pajamas made from natural materials like cotton.
Layered Bedding: Use lightweight blankets that can be easily adjusted.
Avoid Triggers: Limit alcohol, caffeine, and spicy foods, especially before bed.
Stress Management: Practice relaxation techniques such as meditation.

Conclusion

Night sweats are common but can be caused by various factors, ranging from lifestyle and menopause to more serious underlying conditions like infections, certain cancers, and endocrine or neurological disorders. Noting any other accompanying symptoms is vital for diagnosis. Consulting a healthcare provider for a thorough evaluation is essential for determining the cause and appropriate treatment.

For additional information on night sweats and other medical symptoms, you can refer to the extensive resources provided by the Mayo Clinic.

Frequently Asked Questions

No, not always. Many common conditions like menopause, anxiety, or certain medications can cause night sweats. However, persistent or severe episodes, especially with other symptoms like fever or unexplained weight loss, should be evaluated by a doctor.

Infections that cause night sweats are often accompanied by other symptoms such as fever, cough, and fatigue. If you experience night sweats along with these signs, it is important to see a doctor for testing.

Many medications, including antidepressants, hormone therapy drugs, and some pain relievers, can affect the body's thermoregulation and cause night sweats as a side effect. Talk to your healthcare provider about your prescriptions if you suspect this is the cause.

Yes, lifestyle factors such as consuming alcohol before bed, eating spicy food, or having a highly stressed mindset can all contribute to night sweats. Making adjustments like avoiding these triggers and managing stress can help.

Yes. While sleeping in a warm room or with too many blankets can cause sweating, true night sweats are episodes of severe, drenching sweating that are unrelated to your sleep environment and can point to an underlying medical cause.

Idiopathic hyperhidrosis is a condition where the body chronically produces too much sweat without an identifiable medical or environmental cause. When this occurs during sleep, it is considered a form of sleep hyperhidrosis.

You should schedule a visit with your doctor if your night sweats are frequent, interrupt your sleep, or are accompanied by a fever, pain, or unexplained weight loss. A physical exam and possible tests can help determine the cause.