Night sweats in men are common and usually tied to something fixable, like a warm bedroom, stress, or a medication side effect. But when sweating happens regularly and is heavy enough to soak your sheets, it can signal an underlying issue worth investigating. The causes range from simple environmental factors to hormonal shifts, sleep disorders, and occasionally something more serious.
Your Bedroom May Be Too Warm
The simplest explanation is often the right one. An overheated room, heavy blankets, or synthetic bedding can all push your body temperature up enough to trigger sweating overnight. This kind of sweating doesn’t technically count as “night sweats” in a medical sense. True night sweats happen regardless of your sleep environment and range from moderate dampness to drenching episodes that force you to change your sheets.
The National Sleep Foundation recommends keeping your bedroom between 60 and 67°F for optimal sleep. Some sleep researchers suggest an even narrower range of 60 to 65°F. If you’re sweating at night and haven’t checked your thermostat, start there. Switch to breathable cotton or moisture-wicking sheets, ditch the heavy comforter, and see if the problem resolves within a few nights.
Low Testosterone and Hormonal Shifts
Testosterone levels in men decline gradually starting around age 30, and when they drop low enough, one of the more surprising symptoms is night sweats. The mechanism is similar to what women experience during menopause. Your hypothalamus, the part of your brain that acts as a thermostat, becomes more sensitive to small changes in body temperature. When it misreads a minor temperature fluctuation as overheating, it triggers a rapid response: blood vessels in the skin widen, producing a flush of warmth, and the body immediately counters with sweating to cool down. The result is that familiar cycle of feeling hot, then cold and clammy.
Men undergoing treatment for prostate cancer are especially prone to this, since hormone therapy deliberately lowers testosterone. But it also happens naturally as testosterone declines with age. If your night sweats come with low energy, reduced sex drive, or mood changes, low testosterone could be the connection.
Sleep Apnea Is a Major Culprit
Obstructive sleep apnea, where your airway repeatedly collapses during sleep, is one of the most underrecognized causes of night sweats in men. Research published in the European Respiratory Journal found that 31% of people with sleep apnea reported frequent night sweats (three or more times per week), compared to just 11% of the general population. That’s nearly three times the rate.
The connection likely involves your body’s stress response. Each time your airway closes, your oxygen drops and your nervous system fires up to reopen the airway. That repeated activation throughout the night raises your heart rate and blood pressure, generating heat and sweat. The encouraging finding: when people with sleep apnea used a CPAP machine consistently, the rate of frequent night sweats dropped from 33% to about 12%, essentially matching the general population. If you snore heavily, wake up gasping, or feel exhausted despite a full night’s sleep, sleep apnea is worth investigating.
Stress, Anxiety, and Cortisol
Your body doesn’t fully switch off its stress response just because you’re asleep. If you’re going through a high-stress period or dealing with anxiety, your brain can release stress hormones like cortisol, adrenaline, and norepinephrine while you sleep. These hormones increase your heart rate, raise blood pressure, and directly stimulate your sweat glands. The apocrine glands (concentrated in your armpits and groin) are particularly responsive to norepinephrine, which is why stress sweat often feels different and smells stronger than regular exercise sweat.
Nighttime panic attacks can also cause sudden, intense sweating. You might wake up with your heart pounding, drenched in sweat, without any clear nightmare or trigger. These episodes are more common than most men realize, and they don’t always come with the obvious feeling of anxiety you’d associate with a daytime panic attack.
Medications That Cause Night Sweats
Several common medications list night sweats as a side effect. The most frequent offenders include:
- Antidepressants: SSRIs and other depression medications are among the most common drug-related causes of night sweats in men.
- Diabetes medications: Drugs that lower blood sugar can trigger sweating if your blood sugar dips too low overnight.
- Hormone therapy: Used for prostate cancer or other conditions, these directly affect your body’s temperature regulation.
- Opioid-related medications: Including methadone and similar treatments.
If your night sweats started around the same time you began a new medication or changed your dose, the timing probably isn’t a coincidence. Don’t stop a medication on your own, but it’s a conversation worth having with whoever prescribed it. Sometimes a dosage adjustment or switching to a different option in the same class resolves the problem.
Alcohol and Evening Habits
Drinking alcohol before bed is one of the most common and most overlooked causes of night sweats. Alcohol widens blood vessels and raises your skin temperature, then disrupts your sleep cycles as your body metabolizes it. Even moderate drinking (two or three drinks in the evening) can produce noticeable sweating a few hours after you fall asleep. Spicy food, caffeine, and heavy meals close to bedtime can have a similar, if less dramatic, effect. If you’re trying to pinpoint the cause of your sweating, cutting out alcohol for a week or two is one of the easiest experiments to run.
Infections and More Serious Causes
Persistent, drenching night sweats that don’t respond to environmental changes can occasionally point to something that needs medical attention. Infections like tuberculosis, bacterial heart infections, and HIV have long been associated with night sweats. These tend to produce sweating that’s noticeably more severe than what you’d get from a warm room, often soaking through clothing and bedding entirely.
Lymphoma, a cancer of the lymphatic system, is another condition where drenching night sweats are a recognized symptom. The Mayo Clinic notes that lymphoma symptoms often include swollen lymph nodes (in the neck, armpits, or groin), unexplained weight loss, persistent fatigue, fever, and itchy skin alongside the sweating. Having night sweats alone doesn’t mean you have lymphoma, but if sweating comes paired with unexplained weight loss, persistent fevers, or new lumps, those combinations warrant prompt evaluation.
Figuring Out Your Pattern
Night sweats can feel alarming, but narrowing down the cause is often straightforward once you start paying attention to the pattern. Track a few variables for a week or two: your bedroom temperature, what you ate and drank that evening, your stress level, any medications you took, and how severe the sweating was. A clear pattern often emerges quickly. Sweating every night regardless of conditions is more likely to have a medical cause. Sweating only on nights you drink, eat late, or sleep in a warm room points to something you can control directly.
If the sweating is heavy enough to wake you up, happens multiple nights per week, or comes with other symptoms like weight changes, fever, or fatigue, that’s the point where getting bloodwork and a physical exam makes sense. A basic workup can check testosterone levels, thyroid function, blood sugar, and markers of infection, covering the most common medical causes in one visit.