What is the best antifungal for resistant tinea corporis?

From the Guidelines

Treatment of Resistant Tinea Corporis

For the treatment of resistant tinea corporis, terbinafine is recommended as the first-line antifungal agent, administered orally at a dose of 250mg daily for 2-4 weeks, as it appears superior for Trichophyton tonsurans 1.

• Alternatively, itraconazole can be used at a dose of 100mg daily for 15 days, which has shown a superior mycological cure rate of 87% compared to griseofulvin 1.
• The choice of antifungal agent may depend on the specific causative organism, with terbinafine being more effective against Trichophyton tonsurans and itraconazole being effective against a broader range of organisms, including Trichophyton rubrum and Trichophyton mentagrophytes 1.
• In cases of severe or widespread infection, combination therapy with topical and oral antifungals may be considered, although the specific combination and duration of treatment should be individualized based on the patient's response to treatment.
• It is essential to note that oral agents have proven efficacious in the treatment of most cases of tinea corporis, and the treatment regimen should be chosen based on the severity and extent of the infection, as well as the patient's medical history and potential interactions with other medications 1.

From the Research

Treatment Options for Resistant Tinea Corporis

• Terbinafine is an effective treatment for tinea corporis, with mycological and overall efficacy rates of around 90 and 80%, respectively 2, 3.
• However, with rising resistance to terbinafine, itraconazole is being increasingly used as a first-line drug for tinea corporis/cruris 4.
• Itraconazole has been shown to be effective in treating tinea corporis/cruris, with a therapeutic cut-off serum level of >0.2 µg/ml associated with a positive therapeutic outcome 4.
• Other treatment options include fluconazole and griseofulvin, although they may have lower efficacy rates and higher minimum inhibitory concentrations (MICs) compared to itraconazole 5, 4.

Comparison of Antifungal Agents

• Terbinafine has been shown to be more effective than griseofulvin and ketoconazole in treating tinea corporis/cruris 2, 3.
• Itraconazole has been shown to be more effective than fluconazole and griseofulvin in treating tinea corporis/cruris, with lower MICs and higher cure rates 5, 4.
• Topical terbinafine has been shown to be effective in treating tinea corporis/cruris, with mycological cure rates of >80% 3.

Resistance and Treatment Failure

• Resistance to terbinafine is increasing, with high MICs reported in some studies 4.
• Treatment failure with itraconazole is uncommon, but may occur with serum levels of <0.2 µg/ml 4.
• Monitoring of serum levels and adjustment of dosage may be necessary to ensure effective treatment with itraconazole 4.