Also known as: Sleep Hyperhidrosis
Night sweats are episodes of excessive sweating during sleep that can soak through sleepwear and bedding.
Night sweats refer to recurrent episodes of excessive sweating during sleep that are not explained by an overly warm sleeping environment. Unlike normal sweating that occurs when a bedroom is simply too hot, true night sweats can drench sleepwear and bed linens and often wake the person from sleep. They may or may not be accompanied by a feeling of heat or flushing.
Night sweats are extremely common and have a wide range of causes. In women around the time of menopause, they are a well-known symptom driven by hormonal changes that affect the body's temperature regulation. Certain medications — including antidepressants, hormone therapies, and fever-reducing drugs — can also trigger night sweats as a side effect. In other cases, night sweats may be a clue that the body is fighting an infection or dealing with a more serious underlying condition.
The key clinical concern with night sweats is when they are associated with other symptoms such as unexplained weight loss, persistent fever, swollen lymph nodes, or a chronic cough. This combination — often referred to as 'B symptoms' in the context of lymphoma — can indicate a serious underlying illness and always warrants prompt medical evaluation.
There are several possible reasons you may be experiencing Night Sweats. Here are the most common ones.
Fluctuating and declining estrogen levels during perimenopause and menopause disrupt the body's temperature regulation, causing the hypothalamus to incorrectly sense that the body is overheating. This triggers a hot flash or night sweat as the body attempts to cool down through sweating and increased heart rate.
Certain chronic or serious infections — most notably tuberculosis, HIV, endocarditis (infection of the heart valves), and osteomyelitis (bone infection) — can cause drenching night sweats as the immune system battles the invading organism. Night sweats associated with infections are often accompanied by fever and other systemic symptoms.
Many medications can trigger night sweats as a side effect. Common culprits include antidepressants (especially SSRIs and SNRIs), hormone therapies, tamoxifen used in breast cancer treatment, certain blood pressure medications, and fever-reducing drugs like aspirin or ibuprofen, particularly when taken at night.
The body's stress response activates the sweat glands as part of its 'fight or flight' mechanism. In people with anxiety disorders or high chronic stress levels, this activation can occur during sleep — particularly during vivid dreams or nightmares — leading to nighttime sweating.
Hodgkin's lymphoma and non-Hodgkin's lymphoma are cancers of the lymphatic system that can cause drenching night sweats as part of a classic symptom triad that also includes unexplained weight loss and persistent fever. Night sweats from lymphoma are typically severe and recurrent.
An overactive thyroid gland increases the body's overall metabolic rate, causing heat intolerance and excessive sweating throughout the day and night. Other associated symptoms include a rapid heartbeat, tremor, unintentional weight loss, and irritability.
Sleep apnea — a condition in which breathing repeatedly stops and starts during sleep — can trigger night sweats. The physical effort to reopen the airway against the obstruction, combined with the resulting stress on the cardiovascular system, may activate the sweat response.
In some people, excessive sweating — including at night — occurs without any identifiable underlying cause. This condition, called idiopathic hyperhidrosis, involves overactive sweat glands that produce more sweat than the body needs for temperature regulation, and may require specific treatment.
These approaches may help manage night sweats at home. Always consult a healthcare provider if symptoms persist or worsen.
Lowering the room temperature, using a fan, choosing breathable cotton or moisture-wicking bedding, and wearing lightweight sleepwear may significantly reduce the severity of night sweats. For many people — especially those experiencing menopause-related night sweats — a cooler sleep environment can make a meaningful difference.
Spicy foods, alcohol, caffeine, and hot beverages consumed in the evening are known to dilate blood vessels and trigger sweating. Avoiding these triggers in the two to three hours before bedtime may help reduce nighttime sweating episodes.
Practicing calming activities before bed — such as deep breathing, meditation, yoga, or a warm (not hot) bath — may help lower stress and anxiety levels, reducing the likelihood of stress-triggered night sweats. A consistent pre-sleep routine that promotes relaxation can also improve overall sleep quality.
Replacing fluids lost through sweating is important to prevent dehydration overnight. Keeping a glass of water by the bed and drinking adequate fluids throughout the day can help the body manage temperature regulation more effectively.
When evaluating night sweats, a doctor will first review a complete medical history including medications, hormonal status, travel history, and any associated symptoms. A physical examination may reveal signs of infection, lymph node enlargement, or thyroid abnormalities. Blood tests commonly ordered include a complete blood count (CBC), thyroid function tests, blood glucose, and infection markers such as ESR and CRP. In appropriate cases, testing for HIV, tuberculosis, or other infections may be performed. Imaging with a chest X-ray or CT scan may be ordered if lymphoma or a pulmonary condition is suspected.
See a doctor if night sweats are persistent, drenching, and occur regularly, especially if accompanied by unexplained weight loss, fever, persistent cough, or swollen lymph nodes.
Steps you can take to reduce the likelihood of experiencing night sweats.
Keep your sleeping environment cool by using breathable bedding, setting the thermostat between 60 and 67 degrees Fahrenheit, and using a fan or air conditioning if needed.
Avoid alcohol, caffeine, and spicy foods in the evenings, as these can trigger vasodilation and sweating.
If you are on medications that cause night sweats, discuss alternatives or dosing timing adjustments with your doctor — never stop a prescribed medication without medical guidance.
Manage stress and anxiety through regular exercise, mindfulness practices, therapy, or other proven strategies, as these can significantly reduce stress-related night sweating.
Seek regular medical care if you have known risk factors for conditions associated with night sweats — such as HIV, tuberculosis exposure, or a family history of lymphoma — so that any underlying illness can be detected and treated early.
No. While night sweats are a very common symptom of menopause, they can occur in people of any age or sex, and may be caused by medications, infections, anxiety, sleep apnea, thyroid disease, or other conditions. Men and younger women can also experience night sweats for a variety of reasons.
Night sweats alone are rarely a medical emergency, but they become more urgent when accompanied by high fever, severe weight loss, swollen lymph nodes, or persistent cough — symptoms that could indicate a serious infection or cancer. If you experience these symptoms together, see a doctor promptly rather than waiting.
Yes. Frequent night sweats that wake you from sleep, requiring you to change clothing or bedding, can significantly fragment sleep and lead to daytime fatigue, irritability, and difficulty concentrating. Chronic sleep disruption from night sweats is itself a health concern worth addressing, regardless of the underlying cause.
Lymphoma is one possible cause of night sweats, but it is far from the most common one. The vast majority of people with night sweats do not have lymphoma. However, drenching night sweats that occur alongside unexplained weight loss and persistent fever — the classic 'B symptoms' — are a combination that warrants prompt medical evaluation to rule out lymphoma and other serious conditions.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.