In what situations might an immunocompetent patient be prescribed oral antifungals for tinea pedis (athlete's foot)?

From the Guidelines

Oral antifungals may be prescribed for immunocompetent patients with tinea pedis when the infection is severe, extensive, or resistant to topical treatments, with terbinafine being the preferred first-line option due to its high cure rates and favorable safety profile 1. When considering oral antifungal therapy for tinea pedis, the following situations may warrant its use:

• Severe or extensive infections
• Infections resistant to topical treatments
• Moccasin-type tinea pedis with hyperkeratotic involvement
• Infections affecting multiple sites, such as concurrent onychomycosis
• Cases with bacterial superinfection requiring simultaneous antibiotic treatment The choice of oral antifungal agent depends on various factors, including the severity of the infection, patient comorbidities, and potential drug interactions.
• Terbinafine (250 mg daily for 2-6 weeks) is generally the first-line option due to its high cure rates and favorable safety profile 1.
• Itraconazole (200 mg daily for 1-4 weeks or pulse therapy of 200 mg twice daily for 1 week per month for 2 months) and fluconazole (150-300 mg weekly for 2-4 weeks) are alternative options, although fluconazole's efficacy for tinea pedis is not well-established 1. It is essential to monitor patients for potential side effects, including headache, gastrointestinal disturbances, and rarely, liver enzyme abnormalities, and to adjust treatment accordingly. To prevent recurrence, patients should be advised to keep their feet dry, wear breathable footwear, use antifungal powders prophylactically, and treat all affected family members simultaneously. In terms of safety and efficacy, terbinafine has been shown to have a higher cure rate and lower relapse rate compared to itraconazole for dermatophyte infections 1. However, the choice of oral antifungal agent ultimately depends on individual patient factors and the specific clinical scenario.

From the FDA Drug Label

Griseofulvin oral suspension, USP is indicated for the treatment of dermatophyte infections of the skin not adequately treated by topical therapy, hair and nails, namely: Tinea corporis Tinea pedis Tinea cruris Tinea barbae Tinea capitis Tinea unguium Note: Prior to therapy, a dermatophyte should be identified as responsible for the infection The use of this drug is not justified in minor or trivial dermatophyte infections which will respond to topical agents alone.

An immunocompetent patient might be prescribed oral antifungals for tinea pedis in the following situations:

• When the infection is not adequately treated by topical therapy.
• When dermatophyte infection is confirmed by laboratory testing (e.g., KOH preparation, fungal culture) and is caused by one of the specified species of fungi.
• When the infection is severe or extensive, and topical treatment is insufficient. 2

From the Research

Situations for Oral Antifungals in Tinea Pedis

• Immunocompetent patients with tinea pedis may be prescribed oral antifungals in certain situations, including:
  • Chronic conditions where topical treatment has failed 3
  • Extensive or severe infections, such as moccasin foot 3
  • Infections that have spread to other sites, such as the nails 3
  • Patients who have not responded to topical treatment 4, 5
• Oral antifungals, such as terbinafine, itraconazole, and fluconazole, have been shown to be effective in treating tinea pedis 4, 3, 5, 6, 7
• The choice of oral antifungal agent may depend on the severity and extent of the infection, as well as the patient's medical history and potential drug interactions 4, 3, 5

Effective Oral Antifungal Treatments

• Terbinafine 250 mg/day for 2-4 weeks has been shown to be effective in treating tinea pedis 4, 5, 6, 7
• Itraconazole 100-400 mg/day for 1-2 weeks has also been shown to be effective 3, 5, 6
• Fluconazole 150-200 mg/day for 1-2 weeks may be used as an alternative treatment 5
• Intermittent treatment with terbinafine 250 mg/day for 7 days has also been shown to be effective in treating tinea pedis 7

Considerations for Treatment

• The treatment of tinea pedis should be individualized based on the severity and extent of the infection, as well as the patient's medical history and potential drug interactions 4, 3, 5
• Patients should be monitored for adverse effects and treatment efficacy, and the treatment regimen should be adjusted as needed 4, 3, 5