What is the treatment for allergic dermatitis of the foot?

Treatment for Allergic Dermatitis of the Foot

The mainstay of treatment for allergic dermatitis of the foot is topical corticosteroids, with the least potent preparation required to control symptoms, combined with proper skin care measures including emollients and avoidance of irritants. 1

First-Line Treatment Approach

Topical Corticosteroids

• Start with a moderate-potency topical corticosteroid for the foot, as this area typically requires stronger preparations than other body areas 1
• Apply twice daily for 2-4 weeks 1
• For more severe cases, consider a potent corticosteroid such as clobetasol propionate 0.05% cream or lotion 2, 3
  • Clobetasol propionate has shown excellent efficacy in controlling inflammatory dermatoses 3
  • Limit use of potent steroids to 2 weeks to avoid adverse effects 2

Emollients and Skin Care

• Apply emollients liberally and frequently, especially after bathing 1
• Use a dispersible cream as a soap substitute to cleanse the skin 1
• Emollients provide a surface lipid film which retards evaporative water loss 1
• Consider emollient-containing corticosteroid formulations for dry, scaly dermatitis 4

Management of Secondary Complications

Infection Management

• Look for signs of secondary bacterial infection (crusting, weeping) 1
• If infection is present, treat with appropriate antibiotics:
  • Flucloxacillin for Staphylococcus aureus (most common pathogen) 1
  • Phenoxymethylpenicillin for β-hemolytic streptococci 1
  • Erythromycin for penicillin-allergic patients 1

Fungal Infection Considerations

• Rule out or treat concomitant fungal infection (athlete's foot/tinea pedis) 1
• For fungal infection, use:
  • Ciclopirox olamine 0.77% cream or gel applied twice daily for 4 weeks 1
  • For severe cases, consider oral terbinafine 250mg daily for 1-2 weeks 1

Additional Therapeutic Options

Antihistamines

• Sedating antihistamines can be useful for short-term management of severe pruritus 1
• Non-sedating antihistamines have little value in allergic dermatitis 1
• Be aware of potential tachyphylaxis with prolonged antihistamine use 1

Alternative Topical Treatments

• Ichthammol (1% in zinc ointment) or coal tar preparations can be considered for lichenified dermatitis 1
• Tacrolimus 0.1% ointment may be an alternative for patients who cannot tolerate corticosteroids 5

Prevention and Long-term Management

Avoidance of Triggers

• Identify and avoid irritants and allergens 1
• Avoid soaps and detergents which remove natural skin lipids 1
• Wear cotton socks rather than synthetic materials 1
• Keep nails short to minimize trauma from scratching 1

Foot Care Measures

• Thoroughly dry between toes after bathing 1
• Use foot powder after bathing to reduce moisture 1
• Change socks daily and clean footwear periodically 1
• Avoid extreme temperatures and occlusive footwear 1

Common Pitfalls to Avoid

• Undertreatment: Many patients receive inadequate treatment due to fears about topical steroids 1
• Overtreatment: Prolonged use of potent steroids can cause skin atrophy and systemic effects 2
• Missed secondary infection: Always check for bacterial or fungal superinfection 1
• Inadequate patient education: Ensure patients understand proper application techniques and quantities 1
• Failure to address underlying causes: Identify and manage occupational or environmental triggers 1

By following this structured approach to treatment, most cases of allergic dermatitis of the foot can be effectively managed with significant improvement in symptoms and quality of life.