Treatment of Athlete's Foot
Apply topical terbinafine 1% cream twice daily for 1 week to the affected area—this is the first-line treatment for typical interdigital tinea pedis in healthy adults. 1, 2, 3
First-Line Topical Therapy
Terbinafine 1% cream applied twice daily for 1 week is superior to all other topical antifungals because of its fungicidal action, shorter treatment duration, and higher cure rates (78% at end of treatment, 89% at 2-week follow-up). 1, 4, 5
For infection between the toes specifically, use twice-daily application for 1 week; for infection on the bottom or sides of the foot, extend treatment to 2 weeks. 3
Wash the affected skin with soap and water and dry completely before each application, paying particular attention to drying between the toes. 1, 3
Alternative Topical Options (When Terbinafine Unavailable)
Ciclopirox olamine 0.77% cream/gel applied twice daily for 4 weeks achieves approximately 60% cure at end of treatment and 85% cure two weeks after completion—superior to clotrimazole but requires longer treatment than terbinafine. 1, 2
Clotrimazole 1% cream applied twice daily for 4 weeks is less effective than both terbinafine and ciclopirox but remains widely available over-the-counter. 1, 2
When to Use Oral Therapy
Reserve oral antifungals for severe disease, failed topical therapy, concomitant nail infection (onychomycosis), or immunocompromised patients. 1, 2
Oral terbinafine 250 mg once daily for 1-2 weeks provides similar mycological efficacy to 4 weeks of topical clotrimazole but with faster clinical resolution and is the preferred oral agent. 1, 2
Oral itraconazole 100 mg daily for 2 weeks offers comparable efficacy to oral terbinafine but carries a slightly higher relapse rate. 1, 2
Fluconazole is less effective than both terbinafine and itraconazole for dermatophyte infections and should only be considered when other agents are contraindicated or not tolerated. 1
Critical Prevention Measures to Prevent Recurrence
Failure to address these factors is the most common reason for treatment failure:
Examine for concomitant onychomycosis (nail infection), which requires 12-16 weeks of oral terbinafine and acts as a reservoir for reinfection. 1
Treat all infected family members simultaneously to prevent reinfection cycles within households. 1, 2
Decontaminate or discard contaminated footwear, as shoes harbor large numbers of viable fungal spores. If shoes cannot be discarded, seal them in a plastic bag with naphthalene mothballs for at least 3 days, then air them out. 1
Spray terbinafine solution inside shoes periodically to provide ongoing antifungal protection. 1
Apply antifungal foot powder after bathing daily, which reduces infection rates from 8.5% to 2.1%. 1, 2
Change to cotton, absorbent socks daily and wear well-fitting, ventilated shoes. 1, 3
Cover active foot lesions with socks before putting on underwear to prevent spread to the groin area. 1, 2
Safety Monitoring for Oral Terbinafine
Baseline liver function tests and complete blood count are recommended before initiating oral terbinafine in adults with a history of hepatotoxicity or hematologic abnormalities. 1
Monitor for rare but serious adverse events including isolated neutropenia and hepatic failure, particularly in patients with pre-existing liver disease. 1, 2
Common adverse effects include headache, taste disturbance, and gastrointestinal upset. 1
Special Populations
For diabetic patients requiring oral therapy, choose terbinafine over itraconazole due to lower risk of drug interactions and hypoglycemia. 1
Athletes require a minimum of 72 hours of antifungal therapy before return to contact sports, with lesions covered appropriately. 1
For children under 12 years, consult a physician before treatment. 3