Sweating at night

Introduction

Night sweats, also called nocturnal hyperhidrosis, refer to episodes of excessive sweating during sleep that often soak clothing or bedding. While mild sweating during sleep can be normal, persistent or severe night sweats are usually a symptom of an underlying medical condition. They may be associated with infections, hormonal changes, malignancies, or medication side effects. Proper evaluation is essential, as night sweats can sometimes indicate a serious health issue.

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Common Causes of Night Sweating

1. Infections

   • Tuberculosis (TB): Classic cause of drenching night sweats, often accompanied by fever, weight loss, and chronic cough.

   • HIV/AIDS: Can present with fever, weight loss, and night sweats in advanced disease.

   • Bacterial infections: Endocarditis (heart valve infection), osteomyelitis (bone infection), and abscesses may all trigger night sweats.

   • Viral illnesses: Flu-like infections sometimes cause temporary sweating during recovery.

2. Malignancies (Cancers)

   • Lymphoma: Both Hodgkin’s and non-Hodgkin’s lymphoma are strongly associated with night sweats, often described as drenching.

   • Leukemia: Can present with fatigue, weight loss, fever, and sweating.

3. Hormonal Disorders

   • Menopause: Hot flashes and night sweats are hallmark symptoms due to estrogen withdrawal.

   • Andropause (male testosterone decline): May cause sweating episodes in men.

   • Hyperthyroidism: An overactive thyroid gland increases metabolism, causing heat intolerance, sweating, and weight loss.

   • Diabetes (hypoglycemia during the night): Low blood sugar, especially in insulin or sulfonylurea users, may cause sweating.

4. Medications

   • Antidepressants: Especially selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, sertraline, paroxetine.

   • Antipyretics: Aspirin, acetaminophen, and ibuprofen may cause sweating during fever reduction.

   • Hormone therapies: Tamoxifen, raloxifene, and leuprolide can cause hot flashes and sweats.

   • Hypoglycemic agents: Insulin and sulfonylureas (e.g., glipizide, glyburide) may trigger sweating with low blood sugar.

5. Other Causes

   • Obstructive sleep apnea: Repeated awakenings and low oxygen can lead to sweating.

   • Gastroesophageal reflux disease (GERD): Sometimes linked with nocturnal sweating.

   • Neurological disorders: Autonomic neuropathy (common in diabetes) or Parkinson’s disease may affect sweating control.

   • Idiopathic hyperhidrosis: A condition where the body produces excessive sweat without a medical reason.

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Evaluation and Diagnosis

A doctor will usually begin with a detailed medical history and physical examination. Key questions include:

• Duration and frequency of sweating episodes.

• Associated symptoms: fever, weight loss, night-time cough, lymph node swelling, fatigue.

• Current medications.

• Menstrual or menopausal status.

• Lifestyle habits (alcohol, caffeine, substance use).

Investigations may include:

• Blood tests: Complete blood count (CBC), thyroid function tests, blood glucose, liver and kidney function tests, HIV testing if risk factors present.

• Imaging: Chest X-ray (for TB or lymphoma), CT scans if malignancy suspected.

• Cultures: Blood cultures for bacterial infections.

• Sleep study: To evaluate sleep apnea.

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Treatment

Treatment depends on addressing the underlying cause:

1. Infections

   • Tuberculosis: Treated with multi-drug regimen including isoniazid, rifampicin, pyrazinamide, and ethambutol for 6 months or more.

   • Bacterial infections: Treated with antibiotics (e.g., amoxicillin, ceftriaxone, levofloxacin) depending on site and organism.

   • HIV/AIDS: Antiretroviral therapy (ART) controls viral load and reduces sweating.

2. Malignancies

   • Lymphoma or leukemia: Chemotherapy (e.g., CHOP regimen – cyclophosphamide, doxorubicin, vincristine, prednisone for lymphoma) or targeted therapies depending on cancer type.

3. Hormonal Causes

   • Menopause:

     • Hormone replacement therapy (HRT) with estradiol (oral or patch) ± progesterone.

     • Non-hormonal options: venlafaxine, gabapentin, clonidine for hot flashes.

   • Hyperthyroidism:

     • Antithyroid drugs such as methimazole (5–30 mg/day) or propylthiouracil (100–300 mg/day).

     • Beta-blockers like propranolol (20–40 mg three times daily) for symptom control.

   • Diabetes (night-time hypoglycemia):

     • Adjusting insulin dose or type.

     • Bedtime snacks to prevent glucose drops.

4. Medication-Induced Night Sweats

   • Switching antidepressants if SSRIs are the cause (e.g., moving to bupropion).

   • Adjusting hormone therapy under medical guidance.

5. Other Treatments

   • Sleep apnea: Continuous positive airway pressure (CPAP) device.

   • GERD: Proton pump inhibitors like omeprazole (20–40 mg/day).

   • Idiopathic hyperhidrosis:

     • Topical aluminum chloride hexahydrate 20% applied nightly.

     • Oral anticholinergics such as glycopyrrolate (1–2 mg twice daily) or oxybutynin (2.5–5 mg twice daily).

     • Botulinum toxin injections in severe resistant cases.

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Self-Care and Lifestyle Measures

• Maintain a cool bedroom environment with good ventilation.

• Avoid alcohol, caffeine, and spicy foods before bedtime.

• Wear lightweight, breathable clothing.

• Use moisture-wicking bedding.

• Keep a symptom diary (to track triggers and monitor treatment progress).

• Manage stress with relaxation techniques such as yoga, meditation, or breathing exercises.

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When to Seek Medical Help

Immediate medical evaluation is required if night sweats are accompanied by:

• Unexplained weight loss.

• Persistent fever.

• Swollen lymph nodes.

• Chronic cough or chest pain.

• Severe fatigue or weakness.

These may indicate serious infections or malignancies that need urgent treatment.