Men sweat in their sleep for reasons ranging from a warm bedroom to hormonal shifts, medications, and underlying health conditions. While occasional dampness is normal, true night sweats are episodes heavy enough to soak through your clothes or bedding, and they affect a surprisingly large number of men at various life stages.
A Too-Warm Bedroom Is the Simplest Cause
Before looking at medical explanations, it’s worth ruling out the obvious. Waking up sweaty after sleeping under heavy blankets or in a stuffy room isn’t considered true night sweats. Your body naturally drops its core temperature during sleep, and if your environment works against that process, you’ll sweat. The Cleveland Clinic recommends keeping your bedroom between 60 and 67°F (15 to 19°C) for optimal sleep. If your room is warmer than that, the fix may be as simple as adjusting the thermostat or swapping out your bedding.
Declining Testosterone After 40
Testosterone levels drop about 1% per year after age 40, and for some men, that gradual decline is enough to trigger night sweats. The mechanism is similar to what happens during menopause in women: lower levels of sex hormones disrupt the brain’s internal thermostat, located in the hypothalamus. When this thermostat misfires, the nervous system sends signals that widen blood vessels in the skin, producing a sudden flush of warmth. Your body then overcompensates by converting that warm flush into a cold, clammy sweat.
These episodes can happen during the day as hot flashes or at night as drenching sweats. Not every man with declining testosterone will experience them, but the pattern is common enough that hot flashes and sweats are listed among the recognized symptoms of low testosterone. Men who’ve had medical or surgical treatments that sharply reduce testosterone, such as prostate cancer therapy, are especially prone to these vasomotor episodes.
Sleep Apnea and Nighttime Sweating
Obstructive sleep apnea is one of the most overlooked causes of night sweats in men. Research published through the European Respiratory Society found that 31% of people with obstructive sleep apnea reported frequent night sweats (three or more times per week), compared to just 11% in the general population. That’s nearly triple the rate.
The connection makes physiological sense. When your airway collapses during sleep, your body fights to breathe, your heart rate spikes, and stress hormones flood your system. All of that generates heat. If you snore heavily, wake up gasping, or feel exhausted despite a full night’s sleep, sleep apnea may be driving your sweating. Treating the apnea often resolves the sweats.
Medications That Cause Night Sweats
Several common medications list excessive sweating as a side effect, and antidepressants are among the worst offenders. Roughly 20% of patients on antidepressants experience excessive sweating, often concentrated on the scalp, face, neck, and chest. It tends to come in episodic bursts and can persist for as long as you take the medication. Certain antidepressants are more likely to cause it than others, so if sweating becomes a problem, your prescriber may be able to adjust your medication.
Antidepressants aren’t the only culprits. Blood pressure medications, diabetes drugs, and hormone therapies can all trigger nighttime sweating. If your night sweats started around the same time as a new prescription, that timing is worth noting.
Alcohol and Evening Drinking
Drinking alcohol in the evening is a reliable trigger for night sweats. Alcohol raises your heart rate and widens blood vessels in your skin, which pulls heat to the surface and triggers perspiration. This effect is dose-dependent: the more you drink, the more pronounced the sweating.
For men who drink heavily or regularly, there’s an additional layer. Physical dependence on alcohol creates a withdrawal cycle that begins hours after your last drink, often in the middle of the night. Withdrawal activates the sympathetic nervous system, producing sweating, tremors, and a racing heart. Even moderate but consistent drinking can create a mild version of this rebound effect during sleep.
Medical Conditions Worth Knowing About
True night sweats, the kind that drench your sheets and wake you up, can be a symptom of several medical conditions. Some are common and treatable, others are more serious. The list includes:
- Overactive thyroid: Speeds up your metabolism and raises body temperature around the clock, including during sleep.
- Infections: Tuberculosis is the classic example, but bacterial infections, HIV, and other chronic infections can cause recurring night sweats.
- Diabetes: Low blood sugar episodes during the night trigger a stress response that produces sweating, particularly in men taking insulin or certain oral medications.
- Anxiety disorders: Generalized anxiety and social anxiety can activate your fight-or-flight system during sleep, producing sweating alongside a racing heart.
- Certain cancers: Lymphoma in particular lists drenching night sweats as one of its hallmark early symptoms, often accompanied by unexplained weight loss and fevers.
Most men who sweat at night don’t have cancer or a serious infection. But if you’re experiencing repeated drenching episodes with no obvious environmental explanation, especially alongside unexplained weight loss, fevers, or fatigue, those symptoms together warrant medical attention.
What Actually Helps
Start with your sleep environment. Keep the room between 60 and 67°F, and consider what you’re sleeping in and on. Breathable fabrics like bamboo, linen, and merino wool actively pull moisture away from your skin and dry faster than traditional cotton. Cotton absorbs sweat but holds onto it, leaving you damp and uncomfortable. Moisture-wicking sleepwear and sheets can make a meaningful difference for men who run hot at night.
Beyond the bedroom, limiting alcohol in the hours before sleep reduces nighttime vasodilation. Eating spicy food close to bedtime can also trigger sweating through a gustatory response, so shifting those meals earlier in the day helps. Regular exercise improves your body’s overall thermoregulation, though working out too close to bedtime raises your core temperature at exactly the wrong time. Give yourself at least two to three hours between a hard workout and sleep.
If lifestyle changes don’t resolve the problem, the next step depends on the underlying cause. Night sweats from low testosterone, sleep apnea, thyroid issues, or medication side effects each have distinct treatment paths. Tracking when the sweating started, how often it happens, and what else changed around the same time gives you useful information to bring to a medical evaluation.