• See Also
  1. Hot Flashes
  2. Hyperhidrosis
  3. Fever
  • Definitions
  1. Night Sweats
    1. Sweating at night despite sleeping conditions without excessive heat exposure
  • Epidemiology
  1. Common symptom (Prevalence >5-10% depending on age)
  2. Most common at age 41-55 years old (Incidence decreased to 5% after age 65 years)
  • Causes
  1. Malignancy (e.g. Lymphoma or Leukemia)
    1. Typically drenching Night Sweats, easy Bruising or bleeding and Unintentional Weight Loss
  2. Rheumatologic Condition
    1. Takayasu Arteritis (pulseless disease)
    2. Sarcoidosis
    3. Temporal Arteritis (Giant Cell Arteritis)
    4. Rheumatoid Arthritis
  3. Infection
    1. HIV Infection (esp. AIDS and opportunistic infections)
    2. Tuberculosis
    3. Infectious Mononucleosis
    4. Lyme Disease
    5. Fungal infection (Histoplasmosis, Coccidioidomycosis)
    6. Endocarditis
    7. Pneumonia or Lung Abscess
    8. Cysticercosis
  4. Endocrinopathy
    1. Menopause (See Hot Flashes)
    2. Male Hypogonadism (Andropause)
    3. Hyperthyroidism
    4. Diabetes Mellitus
    5. Diabetes Insipidus
    6. Carcinoid Tumor (warm flushed skin with Night Sweats)
    7. Pheochromocytoma (cool and pale skin with Night Sweats)
    8. Obesity
    9. Polycythemia Vera
    10. Autonomic Dysreflexia
  5. Medications
    1. Acetaminophen
    2. Aspirin
    3. Antihypertensives (e.g. Beta Blockers)
    4. Anticholinergics (e.g. Antihistamines)
    5. Phenothiazines
    6. Niacin (Flushing reaction)
    7. Decongestants
    8. Leuprolide (Lupron)
    9. Corticosteroids
    10. Levothyroxine
    11. Protease Inhibitors (Indinavir, Saquinavir)
    12. Monoclonal Antibody (Daclizumab, Rituximab)
    13. Antineoplastics (Interferon alfa-2a, Pegaspargase)
    14. Selective Serotonin Reuptake Inhibitors (e.g. Paroxetine)
    15. Tricyclic Antidepressants
    16. Angiotensin Receptor Blockers (e.g. Losartan)
    17. Selective Estrogen Receptor Modulators (Tamoxifen)
    18. Gonadotropin-Releasing Hormone Agonist
    19. Antiandrogens
    20. Hypoglycemic agents (Oral Hypoglycemics, Insulin)
    21. Efavirenz (Sustiva)
  6. Drugs of Abuse
    1. Alcohol Abuse or Alcohol Withdrawal
    2. Tobacco Abuse
    3. Heroin Abuse and Withdrawal
  7. Miscellaneous Causes
    1. Obstructive Sleep Apnea
    2. Gastroesophageal Reflux (GERD)
    3. Anxiety Disorder
    4. Pregnancy
    5. Syringomyelia
  • Differential Diagnosis
  1. Vasomotor Symptoms of Menopause
  2. Anxiety Disorder (e.g. Panic Attacks, PTSD)
  3. Obesity
  4. Diabetes Mellitus
  5. Gastroesophageal Reflux Disease
  6. Environmental Factors
    1. Excessive heat exposure
    2. Inadequate heat dissipation (e.g. excessive bedding)
  • History
  1. Infectious disease exposure
    1. Febrile Illness
    2. Mononucleosis
    3. Tuberculosis
    4. HIV Infection (esp. AIDS and opportunistic infections including Pneumocystis, Mycobacterium Avium Complex)
    5. Endocarditis (ask about IV Drug Abuse)
    6. Tick Borne Illness (e.g. Lyme Disease)
  2. Travel History
    1. Coccidioidomycosis
    2. Malaria
    3. Tuberculosis
  3. Endocrine symptoms
    1. Menopause (Amenorrhea)
    2. Andropause (e.g. Erectile Dysfunction)
    3. Hyperthyroidism symptoms (anxiety, Diarrhea, Tremor, weight loss, Palpitations)
    4. Hypoglycemia symptoms
  4. Habits
    1. High sugar, high fat diet is associated with increased Night Sweats
      1. Mediterranean Diet in contrast is associated with decreased Night Sweats
    2. Substance Use associated with Night Sweats
      1. Tobacco Abuse
      2. Alcohol use >3 drinks per day
    3. IV Drug Abuse (e.g endocarditis, Drug Withdrawal)
  5. Full Review of Systems for comorbid conditions
    1. Evaluate for causes above
    2. GERD Symptoms (e.g. Bitter or Metallic Taste on awakening)
    3. Obstructive Sleep Apnea symptoms (snoring, witnessed apneas)
    4. Carcinoid Tumor Symptoms (attacks of Abdominal Pain, watery Diarrhea, Flushing, Hypotension)
  • Exam
  • Focused on suspected causes
  1. Body Weight
    1. Evaluate for Unintentional Weight Loss >5% in the past 6-12 months
    2. Cachexia suggests severe prolonged weight loss
  2. Vital Signs
    1. Temperature
      1. Follow Prolonged Fever protocol fo persistent or Recurrent Fever
    2. Blood Pressure
  3. Head and Neck Exam
    1. Thyromegaly (associated with Exophthalmos, Tremor, Tachycardia) may be seen with Hyperthyroidism
    2. Localized or Generalized Lymphadenopathy (esp. if present >4-6 weeks)
    3. Oral Candidiasis (e.g. HIV Infection or AIDS)
    4. Large neck circumference >16-17 cm or Mallampati Score 3-4 are risks for Obstructive Sleep Apnea
  4. Cardiopulmonary Exam
    1. New Heart Murmur (e.g. Endocarditis)
    2. Weak Pulses (Takayasu Arteritis)
  5. Abdominal Exam
    1. Splenomegaly (e.g. Mononucleosis, Lymphoma)
  6. Skin Changes
    1. Petechiae or Purpura
  • Labs
  1. First-line testing
    1. Complete Blood Count (CBC)
    2. Chest XRay
    3. Mono Spot (consider EBV titers)
    4. Purified Protein Derivative (PPD) or Quantiferon for Tuberculosis
    5. Thyroid Stimulating Hormone
    6. HIV Test
    7. C-Reactive Protein
  2. Second-line tests to consider
    1. Blood Cultures (3 sets) if documented nocturnal fever spikes
      1. Include atypicals (e.g. Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
    2. Tick Borne Illness testing (e.g. Lyme Disease, Babesiosis, Anaplasmosis)
    3. Peri-Menopause Confirmation (Follicle Stimulating Hormone, Anti-Mullerian Hormone)
    4. Bone Marrow Biopsy if suspected myeloproliferative or lymphoproliferative disorder
  • Imaging
  1. First-Line Imaging
    1. Chest XRay
  2. Second-Line Imaging
    1. Chest, Abdomen, Pelvis CT with IV contrast
  • Evaluation
  1. Step 1
    1. Evaluate for causes suggested by history and exam
    2. Confirm up-to-date cancer screening appropriate for gender, age and risk factors
    3. Encourage patient to keep a symptom diary along with measured Temperature
    4. Empiric treatment for 4-8 weeks if likely cause identified by history and exam
      1. Proton Pump Inhibitor and lifestyle management trial for Esophageal Reflux
      2. Tobacco Cessation and Alcohol cessation (or decrease)
      3. Decrease or eliminate specifric medication causes
      4. Manage Anxiety Disorder
  2. Step 2
    1. Perform lab testing and first-line imaging as above
  3. Step 3
    1. Empiric treatment (e.g. PPI for GERD) as above, if not already performed
    2. Consider second-line imaging (e.g. CT Chest, Abdomen and Pelvis)
    3. Consider second-line testing as above
  • Management
  1. See Vasomotor Symptoms of Menopause
  2. Treat specific causes (see evaluation and causes as above)
  • Prognosis
  1. Peristent Night Sweats in age >65 years is NOT associated with increased mortality (at least in prmary care)
    1. Mold (2010) J Am Board Fam Med 23(1): 97-103 [PubMed]
  • References
  1. Bryce (2020) Am Fam Physician 102(7): 427-33 [PubMed]
  2. Smetana (1993) JAMA 270:2502-3 [PubMed]
  3. Vera (2003) Am Fam Physician 67(5):1019-24 [PubMed]