Night Sweats

Night Sweats Overview

Doctors in primary care fields often hear their patients complain of night sweats. Night sweats refer to any excess sweating occurring during the night.
In one study of 2267 patients visiting a primary care physician, 41% reported experiencing night sweats during the previous month, so the perception of excessive sweating at night is fairly common.

Night Sweats Causes

Night sweating can arise from harmless situations or serious disease. If your bedroom is unusually hot or you are using too many bedclothes, you may begin to sweat during sleep - and this is normal. In order to distinguish night sweats that arise from medical causes from those that occur because one's surroundings are too warm, doctors generally refer to true night sweats as severe hot flashes occurring at night that can drench sleepwear and sheets, and that are not related to an overheated environment. It is important to note that flushing (a warmth and redness of the face or trunk) may also be hard to distinguish from true night sweats.
There are many different causes of night sweats. Some of the known conditions that can cause night sweats are:

• Menopause: The hot flashes that accompany the menopausal transition can occur at night and cause sweating. This is a very common cause of night sweats in women at or near menopause.
  
• Idiopathic hyperhidrosis: a condition in which the body chronically produces too much sweat without any identifiable medical cause.
  
• Infections: Classically, tuberculosis is the infection most notoriously associated with night sweats. However, bacterial infections, such as endocarditis (inflammation of the heart valves), osteomyelitis (inflammation within the bones), and abscesses all may result in night sweats. Night sweats are also a symptom of AIDS virus (HIV) infection.
  
• Cancers: Night sweats are an early symptom of some cancers. The most common type of cancer associated with night sweats is lymphoma. However, people who have an undiagnosed cancer frequently have other symptoms as well, such as unexplained weight loss and fevers.
  
• Medications: Taking certain medications can lead to night sweats. Antidepressant medications are a common type of medication that can lead to night sweats. All types of antidepressants can cause night sweats as a side effect, with a range in incidence from eight to 22% of persons taking antidepressant drugs. Other psychiatric drugs have also been associated with night sweats. Medicines taken to lower fever such as aspirin and acetaminophen can sometimes lead to sweating. Other types of drugs can cause flushing, which, as mentioned above, may be confused with night sweats. Some of the many drugs that can cause flushing include niacin (taken in the higher doses used for lipid disorders), tamoxifen (Nolvadex), hydralazine (Apresoline), nitroglycerine, and sildenafil (Viagra). Many other drugs not mentioned above, including cortisone medications, such as prednisone and prednisolone, may also be associated with flushing or night sweats.
  
• Hypoglycemia: Sometimes low blood glucose can cause sweating. People who are taking insulin or oral anti-diabetic medications may experience hypoglycemia at night that is accompanied by sweating.
  
• Hormone disorders: Sweating or flushing can be seen with several hormone disorders, including pheochromocytoma, carcinoid syndrome, and hyperthyroidism.
  
• Neurologic conditions: Uncommonly, neurologic conditions including autonomic dysreflexia, post-traumatic syringomyelia, stroke, and autonomic neuropathy may cause increased sweating and possibly lead to night sweats.

  Night Sweats Symptoms

  Excess sweating that occurs at night may drench sheets and bedclothes when severe. As mentioned previously, sometimes the sensation of flushing (a warmth and redness of the face or trunk) may be hard to distinguish from true night sweats or may accompany night sweats. Depending upon the underlying cause of the night sweats, other symptoms may occur in association with the sweating. For example, with certain infections and cancers, fever and chills are associated with the night sweats.
  

  When to Seek Medical Care

  Contact your health care practitioner if you have persistent night sweats that do not resolve or if you have night sweats associated with fevers or any other troubling symptoms.
  

  Exams and Tests

  To determine what is causing night sweats in a particular individual, a doctor must obtain a detailed medical history and often order tests to decide if an underlying medical condition is responsible for the night sweats. Depending upon the cause of the night sweats and an individual's medical history, tests may include blood tests, imaging studies (such as X-rays or CT scans), and further specialized tests.
  

  Night Sweats Treatment

  
  

  Medical Treatment (Medications)

  Night sweats are generally a symptom of an underlying problem that may require medical treatment. However, typically treatment is not directed at the night sweats themselves, but rather at the underlying cause. For examples, hormonal disorders, cancers, and infections are among the causes of night sweats in which treatment is directed at the underlying condition.
  Night sweats arising as a symptom of perimenopause may be treated with hormone therapy, if appropriate. Both estrogen therapy (ET) and combined estrogen and progestin therapy (hormone therapy or HT) have been used successfully to treat symptoms of perimenopause when these become severe or troubling.
  Night sweats arising as a side effect of medications may improve when the medication is discontinued or changed, if appropriate. Your health care practitioner may be able to suggest an alternative form of therapy if you are experiencing severe side effects from taking a medication.
  

  Next Steps

  
  

  Follow-up

  Follow-up care will depend upon the individual situation and the cause of night sweats.
  
  

  Prevention

  Night sweats associated with fevers, infections, cancers, or serious underlying conditions are not preventable.
  

  Outlook

  The prognosis or outlook for an individual will vary according to the underlying health status of the individual as well as the cause of the night sweats. Night sweats associated with the menopausal transition typically improve over time after menopause.
  

  Synonyms and Keywords

  night sweats, night sweat, night flush, night flushing, sweating at night, night sweats in men, menopause and night sweats, hot flashes and night sweats, nightsweats