Night Sweats: Causes, When to Worry & How to Stop Them

Waking up drenched in sweat—sheets soaked, pajamas clinging—is unpleasant and disruptive.Night sweats affect up to 41% of adults, but they're not always harmless. Here's how to distinguish normal sweating from warning signs, plus solutions for sleeping cool and dry.

Night Sweats vs. Being "Too Hot"

First, an important distinction:

• Overheating: Your room is too warm, you have too many blankets, or you exercised before bed. You feel hot and might sweat lightly. The solution is simple: cool your environment.
• True night sweats: Drenching sweats that soak through clothing and bedding, independent of your environment. These occur even in cool rooms and often wake you up.

This article focuses on true night sweats—when something physiological is causing excessive sweating.

Common Causes of Night Sweats

1. Hormonal Changes

Menopause and Perimenopause

The most common cause of night sweats in women. Declining estrogen affects the hypothalamus (body's thermostat), causing "hot flashes" that also occur at night.

• Affects up to 75% of perimenopausal women
• Can begin years before periods stop
• May last 7+ years post-menopause

Low Testosterone (Men)

Declining testosterone in men (especially after age 40) can cause night sweats, similar to the mechanism in menopause.

Hyperthyroidism

An overactive thyroid speeds up metabolism, increasing body temperature and sweating—both day and night.

2. Infections

Night sweats are a classic sign of certain infections:

• Tuberculosis: Classic "night sweats and weight loss" presentation
• HIV: Night sweats are common in both acute infection and AIDS
• Endocarditis: Heart valve infection
• Osteomyelitis: Bone infection
• Abscesses: Pockets of infection in the body

Infection-related night sweats typically come with fever, weight loss, or other symptoms.

3. Medications

Many common medications cause night sweats as a side effect:

• Antidepressants: SSRIs and tricyclics—up to 22% of users experience night sweats
• Hormone therapy: Including tamoxifen and aromatase inhibitors
• Diabetes medications: Especially insulin (from nighttime low blood sugar)
• Pain medications: Aspirin, acetaminophen, opioids
• Blood pressure medications: Some beta-blockers and calcium channel blockers

If night sweats started after beginning a new medication, discuss with your doctor.

4. Sleep Disorders

• Obstructive Sleep Apnea: Breathing interruptions cause stress responses that trigger sweating. Up to 33% of people with OSA report night sweats.
• Nightmares/Night Terrors: Intense dreams trigger fight-or-flight, causing sweating

5. Anxiety and Stress

Chronic anxiety keeps the sympathetic nervous system activated, which can cause sweating during both waking and sleeping hours. Nightmares related to anxiety compound the problem.

6. Alcohol and Substance Use

• Alcohol: Causes blood vessel dilation and interferes with body temperature regulation. Night sweats are especially common during withdrawal.
• Caffeine: Excessive caffeine can trigger sweating
• Drug withdrawal: Opioid, benzodiazepine, and alcohol withdrawal cause severe night sweats

7. When to Worry: Serious Causes

In rare cases, night sweats signal serious conditions:

• Lymphoma and leukemia: Night sweats (drenching), unexplained weight loss, and fatigue are classic warning signs
• Other cancers: Especially carcinoid tumors, pheochromocytoma
• Autoimmune diseases: Rheumatoid arthritis, lupus, vasculitis

When to See a Doctor

Seek medical evaluation if your night sweats:

• Are severe and recurring (happening most nights for 2+ weeks)
• Are accompanied by fever
• Come with unexplained weight loss
• Occur with lymph node swelling
• Started suddenly without explanation
• Are disrupting your sleep significantly
• Come with other concerning symptoms (cough, pain, fatigue)

How to Stop Night Sweats

Optimize Your Sleep Environment

• Keep your bedroom cool: 60-67°F (15-19°C) is ideal
• Use moisture-wicking sheets: Bamboo, Tencel, or performance fabrics
• Choose breathable pajamas: Cotton or moisture-wicking athletic materials
• Use a cooling mattress pad: Gel-infused or water-cooled options exist
• Consider a fan: Air circulation helps regulate body temperature
• Avoid memory foam: It traps heat; consider latex or innerspring

Lifestyle Changes

• Avoid alcohol before bed: Especially within 4 hours of sleep
• Skip spicy foods at dinner: Capsaicin raises body temperature
• Exercise earlier: Not within 4 hours of bedtime
• Maintain healthy weight: Excess weight increases sweating
• Manage stress: Relaxation techniques, therapy, meditation

For Menopause-Related Night Sweats

• Hormone replacement therapy (HRT): Most effective treatment—discuss risks/benefits with your doctor
• Certain antidepressants: Low-dose SSRIs can reduce hot flashes
• Black cohosh: Some evidence for mild benefit (supplement)
• Cooling products: Cooling pillows, mattress pads, and pajamas designed for menopause

For Medication-Related Sweats

If a medication is causing night sweats, talk to your doctor about:

• Adjusting the dose
• Switching to a different medication in the same class
• Taking the medication at a different time of day

Night Sweat Remedies: Quick Reference

Important: While most night sweats have benign causes, recurring drenching sweats— especially with weight loss, fever, or fatigue—should be evaluated by a healthcare provider to rule out serious conditions.