What are the causes and treatment options for hyperhidrosis?

Causes of Hyperhidrosis

Hyperhidrosis is classified into two main categories: primary (focal) hyperhidrosis and secondary hyperhidrosis, with primary hyperhidrosis being the most common form accounting for approximately 93% of all cases. 1

Primary Hyperhidrosis

Primary hyperhidrosis is characterized by:

• Bilaterally symmetric, focal excessive sweating
• Typically affects specific areas: axillae, palms, soles, or craniofacial region
• Onset usually in childhood or adolescence
• No underlying medical condition causing the symptoms
• Often has a genetic component
• Believed to result from sympathetic overactivity 2, 1

Secondary Hyperhidrosis

Secondary hyperhidrosis is caused by an underlying medical condition or medication use and may be focal or generalized. Common causes include:

Medical Conditions

• Endocrine disorders:

  • Hyperthyroidism
  • Diabetes mellitus
  • Pheochromocytoma
  • Hyperpituitarism
  • Menopause

• Neurological disorders:

  • Parkinson's disease
  • Spinal cord injury
  • Stroke
  • Autonomic disorders

• Infectious causes:

  • Tuberculosis
  • Malaria
  • HIV
  • Endocarditis

• Malignancies:

  • Lymphoma
  • Myeloproliferative disorders

• Other conditions:

  • Congestive heart failure
  • Obesity
  • Gout
  • Anxiety disorders 3, 1

Medication-Induced Hyperhidrosis

• Antidepressants (particularly SSRIs)
• Insulin
• Antipyretics
• Opioid withdrawal
• Cholinergic drugs
• Some antihypertensives 1

Special Considerations

Diabetic Autonomic Neuropathy

Diabetic autonomic neuropathy can present with hyperhidrosis, particularly affecting the face and upper body, while the lower extremities may experience anhidrosis (lack of sweating). This can be diagnosed through heart rate variability testing, postural hypotension testing, and other specialized tests 3.

Heat Stress and Environmental Factors

Exposure to extreme heat can exacerbate hyperhidrosis symptoms. Medications that may increase susceptibility to heat-related hyperhidrosis include:

• Loop diuretics
• Serotonergic antidepressants
• Angiotensin-converting enzyme inhibitors
• Proton-pump inhibitors 3

Malignant Hyperthermia

While rare, malignant hyperthermia is a severe condition that can present with hyperhidrosis along with other symptoms like muscle rigidity and high fever. This is typically triggered by certain anesthetic agents and requires immediate medical attention 3.

Diagnostic Approach

When evaluating a patient with hyperhidrosis, consider:

1. Pattern of sweating: Focal vs. generalized
2. Timing: Continuous vs. episodic
3. Triggers: Heat, anxiety, food, exercise
4. Associated symptoms: Weight loss, palpitations, fever
5. Medication history: Recent changes or additions
6. Family history: Primary hyperhidrosis often has a genetic component

The Hyperhidrosis Disease Severity Scale (HDSS) can be used to assess the severity and impact on quality of life, with treatment considered successful when the HDSS score is reduced to less than 2 2, 4.

Treatment Options

Treatment depends on the underlying cause:

For Primary Hyperhidrosis:

1. First-line treatments:

   • Topical aluminum chloride (15% solution) for axillary hyperhidrosis
   • Topical glycopyrrolate for craniofacial hyperhidrosis
   • Iontophoresis for palmar and plantar hyperhidrosis

2. Second-line treatments:

   • Botulinum toxin injections (effective for 3-9 months)
   • Microwave therapy (for axillary hyperhidrosis)
   • Oral anticholinergics (glycopyrrolate, oxybutynin)

3. Surgical options (for severe cases):

   • Local procedures (curettage, liposuction) for axillary hyperhidrosis
   • Endoscopic thoracic sympathectomy as a last resort 2, 4, 5

For Secondary Hyperhidrosis:

Treatment should focus on addressing the underlying condition. For example:

• Treating hyperthyroidism
• Managing diabetes
• Adjusting or changing medications
• Treating infections 1

Complications and Considerations

Untreated hyperhidrosis can lead to:

• Skin maceration
• Secondary bacterial or fungal infections
• Significant psychosocial distress
• Occupational limitations
• Social isolation

Anticholinergic medications should be used with caution in patients with glaucoma, myasthenia gravis, and significant bladder outflow obstruction due to potential side effects 2, 6.

Patients with hyperhidrosis should be advised to avoid extreme temperatures, wear moisture-wicking clothing, and apply cold water regularly to help cool the skin 2.

By understanding the diverse causes of hyperhidrosis and following a systematic approach to diagnosis and treatment, most patients can achieve significant improvement in their symptoms and quality of life.