What are the causes of night sweats (nocturnal hyperhidrosis)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 1, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Night sweats workup should begin with a thorough history and physical examination to identify potential causes, including infections, malignancies, medications, menopause, hyperthyroidism, and anxiety, as these conditions can significantly impact morbidity, mortality, and quality of life 1. The most common causes of night sweats include:

  • Infections (tuberculosis, HIV, endocarditis)
  • Malignancies (lymphoma, leukemia)
  • Medications (antidepressants, hormone therapies)
  • Menopause
  • Hyperthyroidism
  • Anxiety Initial laboratory testing should include:
  • Complete blood count
  • Comprehensive metabolic panel
  • Erythrocyte sedimentation rate
  • Thyroid-stimulating hormone
  • HIV testing For patients with concerning symptoms like weight loss, lymphadenopathy, or persistent fever, additional tests may include:
  • Chest X-ray
  • Tuberculosis testing
  • CT scans of the chest, abdomen, and pelvis A sleep study might be warranted if obstructive sleep apnea is suspected, as sleep disturbances can exacerbate night sweats and impact overall health 1. Management focuses on treating the underlying cause rather than the symptom itself, as this approach can improve morbidity, mortality, and quality of life outcomes 1. While awaiting diagnosis, patients can minimize night sweats by:
  • Keeping the bedroom cool
  • Using moisture-wicking bedding
  • Avoiding alcohol and spicy foods before bedtime
  • Maintaining good sleep hygiene Persistent unexplained night sweats, especially when accompanied by other systemic symptoms, warrant referral to appropriate specialists based on the suspected etiology, as timely and accurate diagnosis is crucial for effective management and improved patient outcomes 1.

From the Research

Definition and Prevalence of Night Sweats

  • Night sweats are a common symptom with a lack of uniform definition and diagnostic guideline 2.
  • The prevalence of night sweats ranges from 10% among older primary care patients to 60% among women on an obstetrics inpatient unit 3.

Causes of Night Sweats

  • Night sweats can be caused by various factors, including infection, malignancies, sleeping disorders, and medication-related issues 2, 4.
  • Other conditions associated with night sweats include menopause, mood disorders, gastroesophageal reflux disease, hyperthyroidism, and obesity 5.
  • Certain medications, such as antihypertensives, antipyretics, and drugs of abuse like alcohol and heroin, can also cause night sweats 4.

Diagnostic Evaluation

  • A thorough history, physical examination, and directed laboratory and radiographic studies can help exclude serious causes of night sweats 4, 5.
  • Laboratory tests, such as a complete blood count, tuberculosis testing, thyroid-stimulating hormone levels, HIV testing, and C-reactive protein level, can be used to evaluate night sweats 5.
  • Imaging studies, such as chest radiography, computed tomography of the chest and/or abdomen, and bone marrow biopsy, may be considered selectively 5.

Treatment and Management

  • Hormone replacement therapy (HRT) is the most effective treatment for managing menopausal hot flushes and night sweats 6.
  • Alternative treatment approaches, such as alpha adrenergic blockers, thalidomide, and thioridazine, may be beneficial for some patients 3.
  • Reassurance and continued monitoring are recommended if no underlying disorder is suspected and laboratory results are normal 5.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

[Night sweats, a common symptom].

Nederlands tijdschrift voor geneeskunde, 2024

Research

Night sweats: a systematic review of the literature.

Journal of the American Board of Family Medicine : JABFM, 2012

Research

Diagnosing night sweats.

American family physician, 2003

Research

Persistent Night Sweats: Diagnostic Evaluation.

American family physician, 2020

Research

Managing menopausal symptoms: hot flushes and night sweats.

Nursing standard (Royal College of Nursing (Great Britain) : 1987), 2013

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.