Night sweats in men are surprisingly common, and they range from harmless to medically significant. About 10% of men in the general population report frequent nighttime sweating (three or more times per week), and for many, the cause is something fixable like a warm bedroom, alcohol before bed, or a medication side effect. But persistent, drenching sweats can also signal conditions worth investigating, from sleep apnea to hormonal shifts to, rarely, something more serious.
Sleep Apnea Is a Leading Cause
One of the most overlooked causes of night sweats in men is obstructive sleep apnea, a condition where the airway repeatedly closes during sleep. Each time the airway collapses, blood oxygen drops and the body kicks into a stress response, raising blood pressure and activating sweat glands. A large Icelandic study found that 31% of men with sleep apnea reported frequent night sweats, compared to just 10% of men without it. That’s a threefold difference.
If your husband snores heavily, gasps or pauses his breathing during the night, or wakes up feeling unrested despite a full night’s sleep, apnea is a strong possibility. The good news: treatment with a continuous positive airway pressure (CPAP) device has been shown to reduce both sweating and elevated blood pressure in these patients. If he hasn’t had a sleep study, this is one of the most practical next steps.
Medications That Trigger Sweating
A long list of common medications can cause night sweats, and many people never connect the two. Antidepressants in the SSRI class (like sertraline or fluoxetine) are among the most well-documented culprits. One study found that people taking SSRIs were about three times more likely to report night sweats. The likely mechanism involves changes in brain chemicals that help regulate body temperature.
Blood pressure medications, particularly a class called angiotensin receptor blockers, carried a similarly elevated risk in that same study, as did thyroid hormone supplements. Other known offenders include over-the-counter pain relievers like aspirin and ibuprofen, diabetes medications, corticosteroids, and opioid pain medications. If your husband started or changed a medication in the weeks before the sweating began, that connection is worth raising with his doctor.
Alcohol and Diet
Drinking alcohol, even moderately, can disrupt the body’s internal thermostat. Alcohol causes blood vessels near the skin to dilate, which initially makes a person feel warm and flushed. It also shifts the brain’s temperature set point, triggering the body to dump heat through sweating as a compensation. On top of that, alcohol alters levels of serotonin and norepinephrine, two brain chemicals directly involved in temperature regulation. The result is a sweaty, restless night, especially during the second half of sleep when the body is metabolizing the alcohol.
Spicy foods, caffeine, and cigarettes close to bedtime can produce similar effects. If the sweating happens mainly on nights when your husband has had a few drinks or a heavy meal, the pattern is likely environmental rather than medical.
Hormonal and Thyroid Issues
Low testosterone is a common cause of night sweats in men, particularly after age 40. Testosterone plays a role in how the brain’s temperature control center (the hypothalamus) sets its thermostat. When levels drop, the hypothalamus can misread normal body temperature as too high and trigger sweating to cool down. This is essentially the same mechanism behind hot flashes during menopause. Other symptoms of low testosterone include fatigue, reduced sex drive, mood changes, and difficulty concentrating.
An overactive thyroid gland (hyperthyroidism) speeds up metabolism across the board, generating excess body heat. Night sweats from thyroid problems typically come with other signs: unexplained weight loss, a racing heart, trembling hands, or feeling anxious without a clear reason. Both conditions are diagnosed with a simple blood test.
Stress and Anxiety
The body’s stress response doesn’t shut off at bedtime. Chronic stress or anxiety keeps the nervous system in a heightened state, and during sleep this can manifest as sweating, a rapid heart rate, or frequent waking. People with anxiety disorders or those going through particularly stressful periods often notice their sweating worsens at night, when the brain is no longer distracted by daytime activity. If your husband is dealing with work pressure, financial stress, or other worries, this may be a contributing factor alongside or instead of a physical cause.
Infections and Serious Conditions
Certain infections are known to cause drenching night sweats. Tuberculosis is the classic example, but HIV, bacterial heart infections (endocarditis), and other chronic infections can produce the same symptom. These conditions almost always come with additional signs like fever, fatigue, or weight loss.
Rarely, night sweats are an early symptom of lymphoma or leukemia. In lymphoma, doctors look for a specific cluster called “B symptoms”: drenching sweats that soak through clothing or sheets, unexplained weight loss of more than 10% of body weight, and recurring fevers or chills. Persistent fatigue, painless swollen lymph nodes in the neck, armpits, or groin, and itchy skin are other warning signs. These cancers are uncommon, but persistent and worsening sweats combined with any of these symptoms warrant prompt evaluation.
Other Medical Conditions
Several other health problems can produce night sweats. Diabetes, particularly when blood sugar drops too low overnight (hypoglycemia), triggers a stress response that includes sweating. Heart disease and heart failure can cause night sweats as the cardiovascular system struggles to regulate itself during sleep. Obesity increases the body’s baseline heat production and insulates the core, making it harder to cool down at night. Even conditions like Parkinson’s disease and certain autoimmune disorders can disrupt the autonomic nervous system’s control of sweating.
Simple Fixes That Help
Regardless of the underlying cause, the sleep environment makes a real difference. Sleep experts recommend keeping the bedroom between 60 and 68 degrees Fahrenheit. Research shows that sleep quality drops noticeably when room temperature climbs above 77 degrees, and at 86 degrees, people spend 5% to 10% more time lying awake.
Bedding matters too. Studies on duvet weight found that lighter blankets required a tighter comfort window of 62 to 72 degrees, while heavier blankets allowed comfortable sleep across a wider range. For someone who sweats at night, a lighter, breathable blanket paired with a cool room is the better combination. Moisture-wicking sheets and sleepwear made from natural fibers like cotton or bamboo can also help manage the discomfort.
Cutting out alcohol, caffeine, spicy food, and vigorous exercise in the two to three hours before bed eliminates the most common lifestyle triggers. If the sweating persists after addressing these basics, a doctor can run targeted blood work, including tests for thyroid function, testosterone levels, blood sugar, and markers of infection or inflammation, to narrow down the cause.