Sweating (excessive)

Excessive sweating, medically termed hyperhidrosis, is a condition in which the body produces more sweat than is necessary for thermoregulation. Unlike normal sweating, which is a response to heat, exercise, or emotional stress, hyperhidrosis occurs unpredictably and may be localized to specific body regions (such as the palms, soles, underarms, or face) or affect the entire body. This condition can cause significant social embarrassment, occupational difficulties, and psychological distress.

---

Types of Hyperhidrosis

1. Primary (Focal) Hyperhidrosis

   • Localized to specific body parts: palms, soles, underarms, face.

   • Often begins in childhood or adolescence.

   • Thought to result from overactivity of sympathetic cholinergic nerves.

   • Not usually related to an underlying disease.

2. Secondary (Generalized) Hyperhidrosis

   • Excessive sweating affects larger body areas or the whole body.

   • Usually caused by an underlying medical condition or medication.

   • Common causes: diabetes mellitus (hypoglycemia), hyperthyroidism, infections (tuberculosis, HIV), menopause (hot flashes), obesity, certain cancers, or medications (antidepressants, opioids, hypoglycemic agents).

---

Causes

Primary Hyperhidrosis

• Overstimulation of eccrine sweat glands by the sympathetic nervous system.

• Genetic predisposition is seen in many cases (often runs in families).

Secondary Hyperhidrosis

• Endocrine disorders: hyperthyroidism, diabetes mellitus, hypoglycemia, pheochromocytoma, menopause.

• Infections: tuberculosis, HIV, malaria, endocarditis.

• Neurological conditions: Parkinson’s disease, spinal cord injuries, peripheral neuropathy.

• Medications: antidepressants (SSRIs, venlafaxine), opioids, propranolol, hypoglycemic drugs (insulin, sulfonylureas).

• Malignancy: lymphoma, leukemia.

• Other causes: obesity, chronic alcohol use, anxiety disorders.

---

Symptoms

• Visible sweating that is disproportionate to the environmental temperature or activity level.

• Localized dampness, especially in palms, soles, underarms, or face.

• Sweating episodes often occur at least once per week in focal hyperhidrosis.

• Associated symptoms in secondary hyperhidrosis depend on the underlying cause (e.g., weight loss and night sweats in tuberculosis or lymphoma, palpitations and tremors in hyperthyroidism).

---

Diagnosis

• History and physical examination: identifying triggers, distribution (localized vs generalized), age of onset, family history, and systemic symptoms.

• Tests for secondary causes:

  • Blood glucose (diabetes, hypoglycemia)

  • Thyroid function tests (hyperthyroidism)

  • CBC and imaging (malignancy, infection)

  • Hormonal assays (pheochromocytoma, menopause).

• Specialized tests: starch-iodine test (to map affected sweat areas), gravimetric sweat measurement.

---

Complications

• Skin issues: fungal infections (athlete’s foot, candida), bacterial infections, intertrigo.

• Social and psychological: embarrassment, low self-esteem, anxiety, depression.

• Functional impairment: difficulty handling papers, tools, or electronics due to excessive palm sweating.

---

Treatment

Treatment depends on whether hyperhidrosis is primary or secondary. In secondary hyperhidrosis, the underlying condition must be treated. In primary hyperhidrosis, direct treatments to control sweating are used.

1. Topical Treatments

• Aluminum chloride hexahydrate (Drysol, Xerac AC)

  • First-line therapy for mild to moderate hyperhidrosis.

  • Mechanism: blocks sweat ducts.

  • Dose: Apply 20% solution to affected area at night, 2–3 times per week, then reduce as sweating improves.

• Topical glycopyrronium (Qbrexza wipes)

  • Anticholinergic agent.

  • Dose: Apply one pre-moistened cloth to underarms once daily.

---

2. Oral Medications (for moderate to severe cases)

• Anticholinergics

  • Glycopyrrolate: 1–2 mg orally 1–2 times daily.

  • Oxybutynin: start with 2.5–5 mg orally daily, can increase to 10–15 mg/day.

  • Side effects: dry mouth, blurred vision, constipation, urinary retention.

• Beta-blockers (e.g., propranolol 10–40 mg before anxiety-inducing events)

  • Useful if sweating is associated with performance anxiety.

• Benzodiazepines (e.g., clonazepam, lorazepam)

  • Occasionally used when hyperhidrosis is strongly anxiety-related.

---

3. Injectables

• Botulinum toxin type A (Botox, Dysport)

  • Blocks acetylcholine release at sweat glands.

  • Effective for axillary, palmar, plantar, and craniofacial hyperhidrosis.

  • Dose: multiple intradermal injections (50–100 units per axilla; 50–100 units per palm/sole).

  • Effect lasts 6–12 months.

---

4. Medical Devices and Procedures

• Iontophoresis

  • Passing a low-voltage electrical current through tap water into the affected area (usually hands and feet).

  • Sessions: 20–30 minutes, 3 times per week initially, then weekly maintenance.

• Microwave thermolysis (MiraDry)

  • Uses microwave energy to destroy sweat glands in underarms.

  • Provides long-term reduction.

---

5. Surgery

• Endoscopic thoracic sympathectomy (ETS)

  • Surgical interruption of sympathetic nerves responsible for sweating.

  • Reserved for severe, disabling hyperhidrosis resistant to all other therapies.

  • Risk: compensatory hyperhidrosis (sweating in other body parts).

---

Lifestyle and Self-Care Measures

• Wear loose, breathable clothing (cotton, moisture-wicking fabrics).

• Use antiperspirants regularly.

• Avoid triggers such as spicy foods, caffeine, and alcohol.

• Maintain a healthy weight.

• Manage stress and anxiety through relaxation techniques.

---

Prognosis

• Primary hyperhidrosis often persists throughout life but can be controlled with treatment.

• Secondary hyperhidrosis usually resolves when the underlying condition is managed.