Night sweats in men have several possible causes, ranging from a too-warm bedroom to hormonal shifts, medications, and underlying health conditions. Occasional sweating during sleep is normal, especially if your room is hot or you’re under heavy blankets. But if you’re regularly waking up with soaked sheets and no obvious environmental explanation, something specific is likely driving it.
Low Testosterone and Your Internal Thermostat
One of the most common and underrecognized causes of night sweats in men is low testosterone. The thermal control center in the hypothalamus, the part of your brain that regulates body temperature, becomes less stable when testosterone levels drop. Your nervous system sends out signals that widen blood vessels in the skin, producing a sudden flush of warmth. Your body then overcorrects by triggering a cold, clammy sweat to bring your temperature back down. This is essentially the same mechanism behind hot flashes in women during menopause, and it happens in men more often than most people realize.
Testosterone levels naturally decline with age, typically starting around 30 and dropping about 1% per year. But other factors can accelerate the decline: obesity, chronic stress, certain medications, and conditions affecting the testes or pituitary gland. If your night sweats come with fatigue, lower sex drive, or difficulty concentrating, low testosterone is worth investigating with a simple blood test.
Sleep Apnea as a Hidden Trigger
Obstructive sleep apnea, where your airway repeatedly collapses during sleep, is significantly more common in men and frequently causes night sweats. Research published in the American Journal of Managed Care found that 18.9% of people with sleep apnea reported night sweats, compared to 12.2% of people without the condition. The sweating appears tied to drops in blood oxygen levels during apnea episodes. Frequent awakenings and the physical effort of restarting breathing increase sympathetic nervous system activity, the same fight-or-flight response that makes you sweat during a stressful moment while awake.
Many men with sleep apnea don’t know they have it. If you snore heavily, wake up gasping, or feel exhausted despite a full night’s sleep, the sweating may be a clue pointing toward a breathing problem rather than a temperature problem.
Medications That Cause Night Sweats
Several commonly prescribed medications list night sweats as a side effect. Antidepressants are among the most frequent culprits, particularly SSRIs and SNRIs. Hormone therapy, medications used to treat diabetes (especially those that can cause blood sugar to drop overnight), and methadone can all trigger sweating during sleep.
If your night sweats started or worsened shortly after beginning a new medication, that timing is a strong signal. Don’t stop taking a prescribed medication on your own, but it’s a conversation worth having with whoever prescribed it. In many cases, adjusting the dose or switching to a different option resolves the problem.
Alcohol, Anxiety, and Lifestyle Factors
Drinking alcohol before bed is one of the most straightforward causes of nighttime sweating. Alcohol increases your heart rate and widens blood vessels in your skin, which directly triggers perspiration. Even moderate drinking can do this. For people who drink heavily and regularly, the picture gets more complicated: physical dependence on alcohol makes withdrawal itself a cause of night sweats, with symptoms that can range from clammy skin to severe sweating and fever in the most dangerous form of withdrawal.
Stress and anxiety also play a role. When your nervous system stays activated at night, the same adrenaline-driven response that causes sweaty palms during the day can trigger generalized sweating during sleep. Eating spicy food or exercising intensely close to bedtime raises your core body temperature and can produce the same result.
When Night Sweats Signal Something Serious
In a small percentage of cases, night sweats point to a condition that needs prompt attention. Lymphoma and leukemia are the malignancies most associated with drenching night sweats. The combination of night sweats with unexplained weight loss and persistent fever is considered a red flag pattern in oncology, particularly when swollen lymph nodes are also present.
Infections can also cause night sweats. Tuberculosis is the classic example, but endocarditis (an infection of the heart valves), HIV, and pneumonia are also on the list. Endocrine conditions beyond low testosterone, including hyperthyroidism and uncontrolled diabetes, can drive nighttime sweating as well. If your sweats are drenching (requiring you to change sheets or clothing), persistent over weeks, and accompanied by weight loss, fever, or new lumps, those symptoms together warrant a medical workup rather than a mattress upgrade.
Hyperhidrosis: When Sweating Is the Condition Itself
Some men simply sweat more than others due to a condition called primary hyperhidrosis. This is caused by overactive nerve signals to sweat glands, not by any underlying disease. It tends to run in families and usually affects specific areas like the palms, feet, underarms, and face rather than the whole body. It often starts in adolescence or early adulthood.
Secondary hyperhidrosis, by contrast, produces sweating across the entire body and is driven by a medical condition or medication. The distinction matters: if your sweating is localized and has been a lifelong pattern, it’s likely primary hyperhidrosis. If it’s generalized, new, and happens mainly at night, it’s worth looking for an underlying cause.
Practical Steps to Reduce Night Sweats
Start with your sleep environment. The Cleveland Clinic recommends keeping your bedroom between 60 and 67°F (15 to 19°C) for optimal sleep. High humidity compounds the problem because sweat can’t evaporate efficiently, so your body keeps producing more of it. A fan, air conditioning, or a dehumidifier can make a noticeable difference. Moisture-wicking sheets and lightweight, breathable sleepwear help your body release heat naturally rather than trapping it against your skin.
Beyond the bedroom, a few changes can help. Avoid alcohol for at least three hours before bed. Skip spicy foods at dinner. If you exercise in the evening, finish your workout at least two to three hours before sleep to give your core temperature time to drop. Keeping a log of when your night sweats occur, how severe they are, and what you ate, drank, or took that day can help you spot patterns and gives useful information if you end up discussing it with a doctor.
If environmental adjustments don’t help and the sweating persists for more than a few weeks, the next step is identifying whether a hormonal imbalance, medication, sleep disorder, or other condition is responsible. A basic evaluation typically involves blood work checking testosterone, thyroid function, blood sugar, and markers for infection or inflammation. If sleep apnea is suspected, an overnight sleep study can confirm it.