Body odour (BO)

Body Odour (Bromhidrosis)

Introduction

Body odour (BO) is a common condition that occurs when sweat secretions are metabolized by skin bacteria into unpleasant-smelling compounds.

• It is most noticeable in the axillae (armpits), feet, and groin, where sweat glands are numerous.

• While it is not dangerous, it can be socially embarrassing and negatively impact quality of life.

• BO may be related to excessive sweating, poor hygiene, diet, or underlying disease.

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Physiology of Sweating

Humans have two main types of sweat glands:

1. Eccrine glands

   • Widely distributed (palms, soles, forehead).

   • Secrete watery sweat for thermoregulation.

   • Normally odourless.

2. Apocrine glands

   • Found in armpits, groin, areolae.

   • Secrete a protein-rich fluid into hair follicles.

   • When broken down by bacteria (e.g., Corynebacterium), produces strong odours.

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Causes of Body Odour

1. Physiological / Lifestyle

• Poor hygiene (irregular washing, dirty clothes).

• Excessive sweating (primary hyperhidrosis).

• Diet: onions, garlic, curry spices, red meat, alcohol, caffeine.

• Stress and anxiety → sympathetic activation → increased apocrine sweat.

2. Medical Causes

• Hyperhidrosis (excessive sweating).

• Diabetes mellitus (sweet/acetone odour).

• Liver failure (musty odour).

• Kidney failure (urine-like odour, “uremic fetor”).

• Trimethylaminuria (fish odour syndrome): Rare genetic disorder.

• Infections: Fungal foot infections, bacterial overgrowth.

• Obesity: Skin folds trap sweat, bacteria, and yeast.

3. Medications

• Antibiotics (alter skin flora).

• Hormonal therapy.

• Psychiatric drugs causing sweating (SSRIs, antipsychotics).

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Clinical Features

• Persistent unpleasant smell from armpits, groin, feet, or body.

• May worsen with heat, exercise, or stress.

• Associated symptoms:

  • Excessive sweating.

  • Skin irritation, fungal infection.

  • Systemic features if underlying disease (e.g., weight loss, fatigue in diabetes).

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Diagnostic Approach

1. History

• Onset, duration, triggers.

• Hygiene, diet, occupation.

• Medical history: diabetes, liver/kidney disease, hyperhidrosis.

• Medications.

• Family history (e.g., trimethylaminuria).

2. Examination

• Distribution: axilla, groin, feet.

• Check for hyperhidrosis (sweat marks, macerated skin).

• Look for infection (fungal, bacterial).

• Signs of systemic disease (liver, kidney, endocrine).

3. Investigations (if persistent / unusual)

• Blood glucose (rule out diabetes).

• Liver and kidney function tests.

• Urinalysis (ketones, uremia).

• Genetic testing for rare metabolic disorders.

• Culture of sweat/skin if infection suspected.

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Management and Treatment

Treatment depends on whether BO is due to hygiene, sweating, or medical causes.

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A. General Lifestyle Measures

• Daily bathing with soap or antibacterial washes.

• Use of deodorants and antiperspirants.

• Regular change of clothes (cotton fabrics better than synthetics).

• Shaving armpits reduces bacterial growth.

• Frequent sock changes and breathable footwear.

• Dietary modifications: reduce spicy foods, garlic, alcohol, caffeine.

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B. Pharmacological Treatment

1. Antiperspirants (for sweating-related BO)

• Contain aluminum chloride which blocks sweat glands.

• Aluminum chloride hexahydrate 20% solution: Apply at night to dry skin, wash off in morning.

2. Topical Antibiotics (reduce skin bacteria)

• Clindamycin 1% topical solution or gel, applied once daily to axilla.

• Erythromycin 2% topical solution, applied twice daily.

• Useful in axillary bromhidrosis due to bacterial overgrowth.

3. Antifungals (if fungal infection in feet/groin)

• Clotrimazole 1% cream applied twice daily × 2–4 weeks.

• Terbinafine 1% cream applied once daily × 1–2 weeks.

4. Oral Medications (for hyperhidrosis or severe cases)

• Anticholinergics (reduce sweating):

  • Oxybutynin 2.5–5 mg orally two to three times daily.

  • Glycopyrrolate 1–2 mg orally two to three times daily.

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

5. Antibiotics (rare, for severe bromhidrosis with infection)

• Doxycycline 100 mg orally once daily × 7–10 days.

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C. Procedural / Advanced Options

1. Botulinum toxin (Botox) injections

   • Blocks acetylcholine release to sweat glands.

   • Effective for axillary hyperhidrosis (lasts 4–6 months).

2. Iontophoresis

   • Low-level electrical current applied to hands/feet in water baths.

   • Reduces sweating in palmar/plantar areas.

3. Microwave therapy (miraDry®)

   • Destroys axillary sweat glands permanently.

4. Surgery (last resort)

   • Endoscopic thoracic sympathectomy (ETS): For severe hyperhidrosis.

   • Excision of apocrine glands: Rarely done.

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Complications

• Social embarrassment, anxiety, depression.

• Skin irritation and infections from chronic sweating.

• Poor quality of life.

• Secondary complications from systemic disease if not recognized (e.g., diabetes).

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Prognosis

• Simple BO: Improves greatly with hygiene and topical treatments.

• Hyperhidrosis-related: Often chronic but manageable with medical/surgical options.

• Systemic disease–related: Prognosis depends on control of underlying condition.

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Patient Education

• BO is common and usually not a sign of poor health.

• Bathe daily and use deodorant/antiperspirant.

• Wear cotton and breathable fabrics.

• Manage diet: limit garlic, spices, alcohol.

• Seek medical advice if:

• BO persists despite good hygiene.

• Associated with weight loss, fever, fatigue.

• Sudden onset of unusual odour (may indicate metabolic disease).