From the Guidelines
Terbinafine should be used for 6 weeks for fingernail infections and 12-16 weeks for toenail infections, as recommended by the British Association of Dermatologists' guidelines for the management of onychomycosis 2014 1. The duration of treatment with terbinafine depends on the specific condition being treated and its severity.
- For fingernail infections, the recommended treatment duration is 6 weeks.
- For toenail infections, the recommended treatment duration is 12-16 weeks. It is essential to complete the full prescribed course, even if symptoms improve earlier, as fungal infections can recur if treatment is stopped prematurely 1. Patients should be aware that while visible improvement may occur within weeks, complete eradication of the fungus, especially in nail infections, takes longer as the healthy nail needs time to grow out. Regular liver function monitoring may be required for extended oral treatment courses, as terbinafine can occasionally cause liver problems. The British Association of Dermatologists' guidelines for the management of onychomycosis 2014 recommend that patients should be re-evaluated 3-6 months after treatment initiation, and further treatment should be given if the disease persists 1. In comparison with itraconazole, terbinafine has been shown to have higher efficacy rates in several large studies, including a multicentre, randomized trial involving 508 subjects 1. Therefore, terbinafine is the preferred treatment option for dermatophyte onychomycosis, and its use should be guided by the recommended treatment durations and patient monitoring.
From the FDA Drug Label
2 DOSAGE AND ADMINISTRATION Fingernail onychomycosis: One 250 mg tablet once daily for 6 weeks. Toenail onychomycosis: One 250 mg tablet once daily for 12 weeks. The recommended duration of treatment with terbinafine is 6 weeks for fingernail onychomycosis and 12 weeks for toenail onychomycosis 2.
From the Research
Duration of Terbinafine Treatment
The duration of terbinafine treatment varies depending on the type and severity of the fungal infection.
- For dermatophyte onychomycosis, oral terbinafine 250 mg/day is typically given for 12 or 16 weeks 3, 4.
- In some cases, treatment may be extended to 24 weeks or more, depending on the severity of the infection and the patient's response to treatment.
- For other types of fungal infections, such as tinea pedis and tinea corporis/cruris, oral terbinafine may be given for 4-6 weeks 5.
- Topical terbinafine 1% formulations may be applied once or twice daily for up to 2 weeks for the treatment of tinea pedis, tinea corporis/cruris, cutaneous candidiasis, and pityriasis versicolor 5.
Special Populations
In special populations, such as children and the elderly, the duration of terbinafine treatment may vary.
- In children, oral terbinafine may be given for 4-6 weeks for the treatment of tinea capitis 5.
- In the elderly, the duration of treatment may be similar to that in adults, but with closer monitoring for potential side effects 4.
- In a case report, a 15-year-old girl with onychomycosis was treated with oral terbinafine continuously for 7 months, with complete healing of the nail mycosis 6.
Treatment Outcomes
The treatment outcomes with terbinafine are generally favorable, with high rates of mycological and clinical cure.
- In randomized controlled trials, terbinafine has been shown to be highly effective in the treatment of dermatophyte onychomycosis, with a meta-average for mycological cure of 76% +/- 3% 4.
- Terbinafine has also been shown to be more effective than other antifungal agents, such as itraconazole and fluconazole, in the treatment of dermatophyte onychomycosis 3, 4.