Night sweats in men are common, and most of the time they trace back to something fixable: a warm bedroom, alcohol, medication, or a sleep disorder. About 10% of men in the general population report frequent nighttime sweating, but that number jumps to over 30% among men with untreated sleep apnea. The cause matters because the fix is different for each one, and occasionally, night sweats signal something that needs medical attention.
Your Sleep Environment May Be the Simplest Cause
Your body needs to drop its core temperature to stay in deep sleep, and it does this by radiating heat through your skin. Research in sleep science shows the optimal bedroom temperature falls between 66 and 70°F (19 to 21°C), with skin temperature settling into a narrow range of about 88 to 95°F. If your room, mattress, or bedding pushes you outside that window, your body compensates by sweating.
Memory foam mattresses trap more heat than innerspring or hybrid designs. Synthetic sheets and heavy comforters do the same. Before looking for a medical explanation, try sleeping in a cooler room with breathable bedding for a week and see if the sweating stops.
Sleep Apnea Is a Major Overlooked Cause
Obstructive sleep apnea, where your airway repeatedly collapses during sleep, is one of the most underdiagnosed causes of night sweats in men. In an Icelandic cohort study of sleep apnea patients, 30.6% of men with the condition reported sweating three or more nights per week, compared to just 9.3% of men without it.
The connection is physiological. Each time your airway closes, your oxygen levels drop and your nervous system fires a stress response to reopen it. That adrenaline surge raises your heart rate, blood pressure, and sweat output. Many men with sleep apnea don’t realize they stop breathing at night. Instead, they notice the secondary effects: waking up drenched, feeling unrested, snoring heavily, or having headaches in the morning.
Treatment with a continuous positive airway pressure (CPAP) machine has been shown to reduce both the objective sweating measurements and the elevated blood pressure that accompany untreated apnea. If you snore, feel exhausted despite sleeping a full night, or your partner has noticed you gasping in your sleep, a sleep study can confirm or rule this out.
Alcohol and Evening Eating Habits
Alcohol is a reliable trigger for night sweats. Drinking increases your heart rate and widens blood vessels near the skin’s surface, both of which ramp up heat loss and sweating. Even moderate drinking in the evening can disrupt your body’s temperature regulation during sleep. If you’re a heavier drinker, the effect compounds: as your blood alcohol level drops in the second half of the night, your nervous system rebounds, and withdrawal symptoms (even mild ones) include sweating and clammy skin.
Spicy food and large meals close to bedtime can have a similar, though less dramatic, effect. Your body generates extra heat during digestion, and capsaicin directly stimulates the same receptors involved in heat perception. If your night sweats happen mostly on nights when you’ve eaten late or had a few drinks, the pattern is the diagnosis.
Medications That Cause Night Sweats
Antidepressants are one of the most common medication-related causes. Estimates put the rate of antidepressant-induced excessive sweating between 4% and 22% of patients, with medications that have stronger effects on the norepinephrine system carrying a higher risk. If your night sweats started within weeks of beginning or adjusting a medication, that timing is significant.
Other drugs commonly linked to nighttime sweating include:
- Blood pressure medications, particularly beta-blockers
- Hormone therapies, including testosterone replacement and medications that suppress testosterone (used in prostate cancer treatment)
- Over-the-counter fever reducers like aspirin and acetaminophen, which work partly by triggering sweating to lower body temperature
- Diabetes medications, especially insulin, if blood sugar drops too low overnight
Don’t stop a prescribed medication because of night sweats, but do bring it up at your next appointment. Dosage adjustments or switching to a different drug in the same class often resolves the problem.
Low Testosterone and Hormonal Shifts
Testosterone plays a role in how the brain’s thermostat regulates body temperature. When levels drop, that thermostat becomes more sensitive and can misread normal body heat as overheating, triggering a sweat response. This is the same basic mechanism behind hot flashes in menopause, and men experience a version of it.
Testosterone levels in healthy, non-obese men between ages 19 and 39 normally range from about 264 to 916 ng/dL, with the median sitting around 531 ng/dL. Levels below 264 ng/dL are considered clinically low. The decline is gradual, roughly 1 to 2% per year after age 30, so night sweats from low testosterone tend to creep in rather than appear suddenly. Other signs include lower energy, reduced sex drive, difficulty building muscle, and mood changes. A simple blood test, ideally drawn in the morning when levels peak, can confirm whether testosterone is a factor.
Infections and Serious Medical Conditions
Most night sweats have a benign explanation, but certain infections and cancers use night sweats as an early warning signal. The distinguishing feature is severity: sweating so heavily that your pajamas, sheets, and blankets are soaking wet. This “drenching” quality is different from waking up slightly damp or clammy.
Tuberculosis is a classic cause, typically accompanied by a cough lasting three or more weeks, unexplained weight loss, fatigue, decreased appetite, and sometimes coughing up blood. In the United States, TB is uncommon but not rare, and risk increases with travel to endemic regions or exposure to someone with active disease.
Lymphoma and other blood cancers can produce drenching night sweats as part of a cluster called B symptoms, which also includes unexplained fever and losing more than 10% of your body weight over six months. HIV infection is another infectious cause, particularly in early or untreated disease. Hyperthyroidism, where the thyroid gland overproduces hormones, can also cause nighttime sweating along with a rapid heartbeat, unintentional weight loss, and anxiety.
These conditions are far less common than the lifestyle and medication causes above. But if your night sweats are new, persistent, drenching, or come with weight loss, fever, or swollen lymph nodes, they warrant a medical workup.
What a Doctor Typically Checks
When there’s no obvious cause from your history, physicians generally follow a systematic approach. The American Academy of Family Physicians recommends starting with a complete blood count (which screens for infections, anemia, and blood cancers), thyroid hormone levels, tuberculosis testing, HIV testing, an inflammatory marker called C-reactive protein, and a chest X-ray. For men specifically, testosterone levels are usually part of that initial panel.
This combination of tests covers the most common and the most serious causes efficiently. Most results come back within a few days, and in the majority of cases, the workup either identifies a treatable cause or provides reassurance that nothing dangerous is happening. Keeping a brief log of when the sweats occur, how severe they are, and what you ate or drank that evening gives your doctor useful information to narrow things down faster.