Sweating at Night: What’s Going On and What You Can Do

Waking up sweaty is annoying and can mess with sleep. Night sweats mean you’re too warm while asleep or your body’s reacting to something else. It can be a one-time thing or a regular problem. Below I’ll cover the likely causes, quick fixes you can try tonight, and signs that mean it’s time to see a doctor. If you have diabetes, pay close attention to the section on blood sugar—this is a common trigger.

Common causes

First, bedroom factors: heavy bedding, a warm room, or non-breathable pajamas can cause sweating. Fix those and sometimes the problem goes away.

Hormones are a big cause. Menopause and perimenopause cause hot flashes and night sweats. Men with low testosterone can also notice more nighttime sweating.

Medications can trigger sweating. Common culprits are antidepressants (SSRIs), some diabetes drugs like insulin or sulfonylureas (they can cause low blood sugar at night), steroids, and some cancer treatments. If you started a new drug and sweated soon after, mention it to your doctor.

Infections and illnesses — like tuberculosis, endocarditis, or even a bad flu — can cause true night sweats, often with fever, weight loss, or feeling generally unwell. Thyroid overactivity (hyperthyroidism) raises metabolism and can lead to sweating too.

Sometimes anxiety or stress shows up as night sweats. Your nervous system can get overactive and raise body temperature while you sleep.

Quick fixes and when to see a doctor

Start with the easy stuff: turn the thermostat down to around 60–67°F (15–19°C), use breathable cotton sheets, and switch to moisture-wicking sleepwear. A fan helps move air and cool skin fast. Avoid spicy foods, alcohol, and caffeine in the evening—these raise body temperature and trigger sweating.

If you have diabetes, check your bedtime and early-morning blood sugar. Low glucose overnight can cause sweating, nightmares, or waking drenched. Talk to your care team about adjusting insulin or sulfonylurea timing or dose. Using a continuous glucose monitor (CGM) can catch overnight lows you won’t notice.

Keep a short log: note room temp, meds, food or drink before bed, and any symptoms. That makes it easier to spot patterns and helps your clinician diagnose the cause.

See a doctor if your night sweats are new and unexplained, happen every night, or come with fever, weight loss, swollen lymph nodes, chest pain, or shortness of breath. Also get checked if you suspect a medication or if blood sugar issues might be the cause.

Most causes are manageable once identified. Don’t ignore ongoing night sweats—getting the right simple fixes or a quick medical check can get your sleep back on track.