From the Guidelines
Terbinafine should be considered as the first choice for treating dermatophyte onychomycosis due to its higher efficacy and tolerability compared to itraconazole. When treating onychomycosis with terbinafine, the recommended dose is 250 mg per day for 6 weeks in fingernail and 12–16 weeks in toenail infection 1. Key points to consider when prescribing terbinafine include:
- Re-evaluating patients 3–6 months after treatment initiation and providing further treatment if the disease persists 1
- Being aware of potential side effects such as gastrointestinal disturbances, headache, and skin reactions
- Considering liver function tests before and during treatment, as oral terbinafine may affect liver function
- Ensuring patients complete the full course of treatment to prevent recurrence of fungal infections
- Consulting healthcare providers before using terbinafine for patients with liver disease or those taking certain medications due to potential interactions. Studies have demonstrated higher efficacy rates for terbinafine compared to itraconazole, with a multicentre, randomized trial showing complete cure in 55% of patients receiving 16 weeks of continuous terbinafine, compared to 26% of patients receiving pulsed itraconazole 1. Long-term follow-up has also shown mycological cure without a second therapeutic intervention in 46% of terbinafine-treated patients, compared to 13% of itraconazole-treated patients 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Terbinafine Overview
- Terbinafine is an allylamine antifungal agent with fungicidal activity against a wide variety of dermatophytes, moulds, and certain dimorphic fungi, and fungistatic activity against Candida albicans 2.
- It is effective in the treatment of superficial dermatophyte infections such as onychomycosis, tinea pedis, and tinea corporis/cruris, achieving mycological cure in > 80% of patients 2, 3.
Efficacy and Safety
- Oral terbinafine is more effective than continuous or intermittent itraconazole in dermatophyte onychomycosis, and is as effective as itraconazole 400 mg/day in tinea pedis 2.
- Topical terbinafine 1% formulations are effective when applied once or twice daily for up to 2 weeks, achieving mycological cure in > 80% of patients with tinea pedis, tinea corporis/cruris, cutaneous candidiasis, and pityriasis versicolor 2.
- Terbinafine is well tolerated after oral or topical administration and has a relatively low potential for drug interactions 2, 3, 4, 5.
Treatment Regimens
- A quarterly terbinafine pulse regimen can be a possible alternative for treating onychomycosis caused by dermatophytes, with no statistical differences regarding effectiveness or side effects compared to conventional treatment regimens 6.
- Topical terbinafine has high efficacy as a cure for tinea pedis, irrespective of type of pharmaceutical formulation, treatment duration, and frequency of application, including a one-shot regimen 4.
Comparison with Other Antifungal Agents
- Terbinafine demonstrates a good safety profile and relatively few drug interactions have been identified, making it a potential front-line drug for some superficial infections responding poorly to the current standard of therapy 5.
- The efficacy of terbinafine may be as good or better than that of the azole antifungals, and it is more effective than griseofulvin in the treatment of tinea pedis and tinea unguinum 2, 5.