Treatment of Foot Fungus
For aggressive or severe foot fungus (tinea pedis), oral terbinafine 250 mg once daily for 2 weeks is the most effective first-line treatment, particularly for extensive, moccasin-type, or treatment-resistant infections. 1
Treatment Algorithm Based on Disease Severity
Mild to Moderate Localized Disease
- Topical antifungal therapy is the mainstay for superficial or localized tinea pedis, applied once to twice daily for 1-6 weeks 2
- Topical allylamines (terbinafine) are preferred over azoles due to superior efficacy and shorter treatment duration 1, 2
- Alternative topical agents include azoles (ketoconazole, clotrimazole), ciclopirox, tolnaftate, and amorolfine 2
Severe or Extensive Disease Requiring Oral Therapy
Oral antifungals should be used when:
- Severe or extensive disease is present 1
- Topical therapy has failed 1, 2
- Moccasin-type or vesiculobullous forms are present 1
- Concomitant onychomycosis exists 1, 3
- Patient is immunocompromised or diabetic 1, 2
Oral terbinafine 250 mg once daily for 2 weeks is the preferred systemic treatment, with over 70% oral absorption and fungicidal action 1. Terbinafine demonstrates superior efficacy against dermatophytes compared to azoles, with lower minimum inhibitory concentrations 1. Evidence from comparative trials shows terbinafine is significantly more effective than griseofulvin (RR 2.26,95% CI 1.49-3.44) 4.
Alternative oral options include:
- Itraconazole (flexible dosing, though slightly lower efficacy and potentially higher relapse rates) 1
- Fluconazole (effective but less studied for this indication) 5, 2
For diabetic patients, terbinafine is specifically preferred over itraconazole due to lower risk of drug interactions and hypoglycemia 1.
Monitoring Requirements
Before initiating oral terbinafine:
- Obtain baseline liver function tests and complete blood count, particularly in patients with history of hepatotoxicity or hematological abnormalities 1, 3
Prevention of Recurrence
Environmental decontamination is critical because T. rubrum persists in hotel bedrooms, carpeting, gyms, and public bathing facilities 6:
- Discard all old, contaminated footwear or decontaminate by placing naphthalene mothballs in shoes, sealing in plastic bags for minimum 3 days 6, 1, 3
- Apply antifungal powders (miconazole, clotrimazole, or tolnaftate) inside shoes regularly 6, 1, 3
- Alternatively, spray terbinafine solution into shoes periodically 6
Daily preventive measures:
- Apply foot powder after bathing 1
- Thoroughly dry between toes after showering 1
- Change cotton, absorbent socks daily 6, 3
- Keep toenails trimmed short 6, 3
- Avoid sharing nail clippers with family members 6, 3
- Wear protective footwear in public bathing facilities, gyms, and hotel rooms 6, 3
- Clean athletic footwear periodically 1
Treat all infected family members simultaneously because both onychomycosis and tinea pedis are contagious 6.
Common Pitfalls to Avoid
- Inadequate treatment duration leads to recurrence—failing to extend treatment in severe cases is a common error 1
- Overlooking concomitant onychomycosis requires longer systemic therapy (12 weeks for toenails) 3
- Failing to address dermatophytomas (dense white lesions beneath the nail) can result in treatment resistance without prior mechanical removal 6
- Not treating environmental sources allows reinfection from contaminated footwear and surfaces 6, 1
Agents to Avoid
Griseofulvin is not recommended as first-line therapy due to lower efficacy, longer treatment duration, and greater drug interactions 1.