What is the treatment for tinea pedis?

Treatment of Tinea Pedis

For uncomplicated interdigital tinea pedis, apply topical terbinafine 1% cream twice daily for 1 week, which is superior to longer courses of other antifungal agents and achieves cure rates exceeding 90%. 1, 2

First-Line Topical Therapy

Terbinafine (Preferred Agent)

• Terbinafine 1% cream applied twice daily for 1 week is the most effective topical treatment, achieving 93.5% mycological cure rates and 89.7% effective treatment rates 3
• For interdigital tinea pedis (between the toes): apply twice daily for 1 week 1, 2
• For plantar tinea pedis (bottom or sides of foot): apply twice daily for 2 weeks 2
• Terbinafine's fungicidal action allows for significantly shorter treatment duration compared to fungistatic agents like azoles 1, 4
• Wash affected skin with soap and water and dry completely before applying 2

Alternative Topical Agents

• Ciclopirox olamine 0.77% cream/gel achieves approximately 60% cure at end of treatment and 85% two weeks post-treatment 1
• Clotrimazole 1% cream is less effective than terbinafine (73.1% vs 93.5% mycological cure) but widely available over-the-counter 1, 3
• Azole creams typically require twice daily application for 4 weeks, making compliance more challenging 5

Oral Therapy for Severe or Resistant Disease

Reserve oral antifungals for extensive disease, failed topical therapy, concomitant onychomycosis, or immunocompromised patients. 1, 6

First-Line Oral Agent

• Terbinafine 250 mg once daily for 1-2 weeks is the most effective oral treatment, with fungicidal action and over 70% oral absorption unaffected by food 1
• For extensive tinea pedis, extend treatment to 2 weeks 1

Alternative Oral Agents

• Itraconazole offers flexible dosing: 100 mg daily for 2 weeks, or pulse dosing at 200-400 mg daily for 1 week per month 1, 7
• Itraconazole should be taken with food and acidic pH for optimal absorption 7
• Itraconazole has similar mycological efficacy to terbinafine but may have slightly higher relapse rates 1
• Fluconazole 150 mg once weekly is less effective than both terbinafine and itraconazole but has fewer drug interactions 1, 7

Critical Adjunctive Measures to Prevent Recurrence

• Apply foot powder after bathing, which reduces tinea pedis rates from 8.5% to 2.1% 1, 7
• Change socks daily and clean athletic footwear periodically 1, 7
• Thoroughly dry between toes after showering 1
• Examine and treat concomitant onychomycosis, as nail infection serves as a reservoir for reinfection 7
• Treat all infected family members simultaneously to prevent reinfection 1, 7
• Cover active foot lesions with socks before wearing underwear to prevent spread to groin 1
• Examine hands, groin, and body folds for secondary infection sites, present in 25% of cases 1, 7

Special Population Considerations

Diabetic Patients

• Prefer terbinafine over itraconazole due to lower risk of drug interactions and hypoglycemia 1
• Up to one-third of diabetics have onychomycosis, which significantly predicts foot ulcer development 1

Athletes

• Require minimum 72 hours of antifungal therapy before return to contact sports 1
• Cover lesions with gas-permeable dressing followed by underwrap and stretch tape 1
• Exclude from swimming pools until treatment initiated 1

Pediatric Patients

• For children 12 years and older, use same terbinafine dosing as adults 2
• For children under 12 years, consult a physician 2

Management of Treatment Failure

Before switching therapy, obtain fungal cultures after discontinuing antifungals for a few days to verify true treatment failure. 7

Common Causes of Apparent Failure

• Poor compliance with treatment regimen 7
• Inadequate drug penetration 7
• Bacterial superinfection 7
• Reinfection from untreated nails or contaminated footwear 7
• Untreated infection at other body sites or in family members 7

Second-Line Approach

• Switch to oral itraconazole if terbinafine fails 7
• Monitor liver function tests at baseline and during prolonged therapy 7
• Consider culture at end of treatment to confirm mycological clearance 7

Key Pitfalls to Avoid

• Do not treat feet in isolation—failure to address nail involvement or other body sites leads to recurrence 7
• Do not neglect contaminated footwear as a source of reinfection 1
• Continue treatment for at least one week after clinical clearing of infection 8
• Do not assume drug resistance without ruling out compliance issues and environmental reinfection sources 7