What is the recommended treatment for an individual presenting with athlete's foot (tinea pedis)?

Treatment of Athlete's Foot (Tinea Pedis)

For interdigital (between-the-toes) athlete's foot, apply topical terbinafine 1% cream twice daily for 1 week, which provides superior efficacy and faster resolution than other topical agents. 1, 2, 3

First-Line Topical Treatment

Terbinafine 1% Cream (Preferred)

• Apply twice daily for 1 week for interdigital infections (between the toes), or twice daily for 2 weeks for infections on the bottom or sides of the foot 1, 3
• Achieves 78% combined mycologic and clinical cure at end of treatment, and 89% at 2-week follow-up 4
• Offers fungicidal action allowing shorter treatment duration compared to other agents 1, 2
• FDA-approved for adults and children 12 years and older 3

Alternative Topical Options

• Ciclopirox olamine 0.77% cream/gel applied twice daily for 4 weeks achieves approximately 60% cure at end of treatment and 85% two weeks after treatment, superior to clotrimazole 1, 2
• Clotrimazole 1% cream applied twice daily for 4 weeks is less effective than terbinafine but widely available over-the-counter 1
• Miconazole applied twice daily for 4 weeks is another over-the-counter option 5

Oral Therapy for Severe or Resistant Cases

Reserve oral antifungals for severe disease, failed topical therapy, concomitant nail infection (onychomycosis), or immunocompromised patients. 2

Oral Terbinafine (First-Line Systemic)

• 250 mg once daily for 1-2 weeks provides similar mycological efficacy to 4 weeks of topical clotrimazole but with faster clinical resolution 1, 2, 6
• Has fungicidal action with over 70% oral absorption unaffected by food 2
• Monitor for rare but serious adverse events: occasional isolated neutropenia and rare liver failure, particularly in patients with preexisting liver disease 1, 6

Alternative Oral Options

• Itraconazole 100 mg daily for 2 weeks has similar mycological efficacy to terbinafine but may have slightly higher relapse rate 1, 2
• Pulse dosing of itraconazole 200-400 mg per day for 1 week per month is an alternative regimen 2
• Fluconazole is less effective than both terbinafine and itraconazole for dermatophyte infections but may be useful when other agents are contraindicated due to fewer drug interactions 2
• Griseofulvin is not recommended as first-line therapy due to lower efficacy (30-40% cure rates) and longer treatment duration 2

Essential Prevention Measures

Preventing recurrence requires addressing both personal hygiene and environmental contamination. 2

Daily Foot Care

• Thoroughly dry between toes after showering to prevent moisture accumulation that promotes fungal growth 1, 2
• Change socks daily and wear cotton, absorbent socks 2, 6
• Clean athletic footwear periodically to eliminate fungal reservoirs 1, 2
• Wear well-fitting, ventilated shoes and change shoes at least once daily 3, 5

Proven Prevention Strategies

• Applying foot powder after bathing reduces tinea pedis rates from 8.5% to 2.1% 1, 2
• Use antifungal powders containing miconazole, clotrimazole, or tolnaftate inside shoes 2
• Wear protective footwear in public bathing facilities, gyms, and hotel rooms 2

Environmental Decontamination

• Discard old, moldy footwear when possible, or place naphthalene mothballs in shoes and seal in plastic bag for minimum 3 days 2
• Spray terbinafine solution into shoes periodically 2
• Treat all infected family members simultaneously to prevent reinfection 2
• Avoid sharing toenail clippers and keep nails as short as possible 2

Critical Pitfalls to Avoid

• Failing to examine for concomitant onychomycosis (nail infection), which requires longer treatment and serves as a reservoir for reinfection 2
• Neglecting to address contaminated footwear as a source of reinfection leads to recurrence 2
• Not treating all infected family members simultaneously results in reinfection 2
• Cover active foot lesions with socks before wearing underwear to prevent spread to groin area (tinea cruris) 1, 2

Special Populations

Athletes

• Require minimum 72 hours of antifungal therapy before return to contact sports 6
• Cover lesions with gas-permeable dressing followed by underwrap and stretch tape 6
• Exclude from swimming pools and discourage barefoot walking in locker rooms until treatment initiated 6

High-Risk Patients

• Risk factors include: swimming, running, warm humid environments, male gender, obesity, and diabetes 1, 2, 6
• For diabetic patients, prefer terbinafine over itraconazole due to lower risk of drug interactions and hypoglycemia 2
• Up to one-third of diabetics have onychomycosis, which significantly predicts foot ulcer development 2

Follow-Up Considerations

The definitive endpoint for adequate treatment should be mycological cure, not just clinical response. 6 Consider follow-up with repeat mycology sampling at the end of standard treatment period, particularly for recurrent or resistant cases 6.