What is the optimal treatment for a 70-year-old man with severe tinea pedis, onychomycosis, and tinea cruris, who is intolerant to terbinafine and taking rosuvastatin (for hyperlipidemia)?

From the Guidelines

For a 70-year-old man with severe tinea pedis, onychomycosis, and tinea cruris who cannot tolerate terbinafine and takes rosuvastatin, the best treatment option would be oral fluconazole, given its suitability as an alternative in patients unable to tolerate terbinafine, as noted in the British Association of Dermatologists' guidelines 1. Given the patient's intolerance to terbinafine and the need for an alternative treatment, fluconazole emerges as a viable option. The British Association of Dermatologists' guidelines suggest that fluconazole 450 mg per week for 3 months in fingernail infections, and for at least 6 months in toenail infections, may be a useful alternative in patients unable to tolerate terbinafine or itraconazole 1.

Key considerations for the treatment include:

• The patient's age and potential for drug interactions, particularly with rosuvastatin, although fluconazole is a weaker inhibitor of the cytochrome P450 enzymes than itraconazole, suggesting fewer drug interactions 1.
• The severity of the infections, which may require a comprehensive approach including both oral and topical treatments.
• The importance of monitoring for adverse effects, which are common with fluconazole, including headache, skin rash, gastrointestinal complaints, and insomnia, and can lead to treatment discontinuation, especially at higher doses 1.

In terms of specific treatment regimen, fluconazole 450 mg once weekly for at least 6 months for toenail onychomycosis, alongside topical antifungal treatment for tinea pedis and tinea cruris, is recommended. Topical treatments such as ciclopirox 8% solution for the nails and ciclopirox or econazole cream for the skin infections could be applied daily or twice daily for an appropriate duration, such as 4 weeks for the skin infections. It is crucial to monitor the patient for signs of adverse effects and to adjust the treatment plan as necessary to ensure the best outcome in terms of morbidity, mortality, and quality of life.

From the FDA Drug Label

The safety and efficacy of once daily use of JUBLIA for the treatment of onychomycosis of the toenail were assessed in two 52-week prospective, multicenter, randomized, double-blind clinical trials in subjects 18 years and older (18 to 70 years of age) with 20% to 50% clinical involvement of the target toenail, without dermatophytomas or lunula (matrix) involvement Efinaconazole has been shown to be active against isolates of the following microorganisms, both in vitro and in clinical infections. Efinaconazole exhibits in vitro minimum inhibitory concentrations (MICs) of 0. 06 mcg/mL or less against most (≥90%) isolates of the following microorganisms: Trichophyton rubrum Trichophyton mentagrophytes JUBLIA is for external use only and is not for oral, ophthalmic, or intravaginal use. It is for use on toenails and immediately adjacent skin only.

The optimal treatment for a 70-year-old man with severe tinea pedis, onychomycosis, and tinea cruris, who is intolerant to terbinafine and taking rosuvastatin (for hyperlipidemia) is efinaconazole (JUBLIA), as it is effective against the microorganisms that cause these conditions, including Trichophyton rubrum and Trichophyton mentagrophytes. However, it is essential to note that efinaconazole is only approved for the treatment of onychomycosis of the toenail, and its use for tinea pedis and tinea cruris would be off-label. Additionally, the patient's age (70 years) is outside the studied age range (18 to 70 years) in the clinical trials, and caution should be exercised when using efinaconazole in this patient population 2.

From the Research

Treatment Options for Severe Tinea Pedis, Onychomycosis, and Tinea Cruris

Given the patient's intolerance to terbinafine and concurrent use of rosuvastatin, alternative treatment options must be considered.

• Itraconazole is a viable option, as it has been shown to be effective in treating dermatophyte infections, including onychomycosis, tinea pedis, and tinea corporis/cruris 3, 4, 5.
• The efficacy of itraconazole in treating these conditions has been demonstrated in various studies, with mycological cure rates ranging from 76% to 91.8% 3, 5.
• Itraconazole can be administered in a pulse therapy regimen, which has been shown to be effective and safe in treating tinea pedis, tinea corporis/cruris, and onychomycosis 3, 4.

Considerations for Treatment

When selecting a treatment option, it is essential to consider the patient's medical history, including their intolerance to terbinafine and use of rosuvastatin.

• There is no direct evidence to suggest a drug interaction between itraconazole and rosuvastatin; however, it is crucial to monitor the patient for potential interactions.
• The patient's age and immunocompetent status should also be taken into account when selecting a treatment option, as older adults may be more susceptible to adverse effects 6.

Alternative Treatment Options

While itraconazole is a viable option, other treatment alternatives may be considered, including topical antifungal agents.

• However, the patient's severe tinea pedis, onychomycosis, and tinea cruris may require systemic treatment, making itraconazole a more suitable option 7, 5.