From the Guidelines
Terbinafine is effective in treating ringworm (tinea infections) and is particularly effective against dermatophytes, the fungi that cause these infections. The dosage of terbinafine varies depending on the location and severity of the infection, as well as the patient's weight. For example, for tinea capitis (scalp ringworm), the dose is 125-250 mg per day for 2-4 weeks for children weighing 20-40 kg and > 40 kg, respectively 1. Terbinafine works by inhibiting the fungal enzyme squalene epoxidase, which disrupts ergosterol synthesis in the fungal cell membrane, leading to fungal cell death.
Some key points to consider when prescribing terbinafine include:
- The medication is generally well tolerated, but patients should monitor for side effects such as headache, gastrointestinal upset, rash, or liver function abnormalities 1.
- Those with liver disease or taking certain medications may need dose adjustments or alternative treatments 1.
- For optimal results, patients should complete the full prescribed course even if symptoms improve before finishing treatment.
- Terbinafine has a high cure rate and low relapse rate compared to other antifungal agents, such as itraconazole and griseofulvin 1.
- The medication is available in oral tablet form and can be given once daily, making it a convenient treatment option for patients 1.
Overall, terbinafine is a effective treatment option for ringworm infections, and its efficacy and safety have been demonstrated in numerous studies 1.
From the Research
Effectiveness of Terbinafine in Treating Ringworm
- Terbinafine is an allylamine antifungal agent that has fungicidal activity against a wide variety of dermatophytes, moulds, and certain dimorphic fungi, and fungistatic activity against Candida albicans 2.
- Oral terbinafine 250 mg/day is effective in the treatment of superficial dermatophyte infections such as onychomycosis, tinea pedis, and tinea corporis/cruris, generally achieving mycological cure in > 80% of patients 2.
- Terbinafine is also effective in children with tinea capitis when administered orally in the dosage range 62.5 to 250 mg/day for 4 weeks 2, 3.
- Comparative data indicate that 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.
- Terbinafine has shown greater efficacy than griseofulvin in dermatophyte onychomycosis, tinea pedis, and tinea corporis/cruris, and comparable efficacy in children with tinea capitis 2, 4, 5.
Cure Rates and Treatment Outcomes
- Cure rates of 96%, 88%, and 84% were achieved with griseofulvin, terbinafine, and fluconazole, respectively, in the treatment of tinea capitis 5.
- In the treatment of tinea imbricata, significant remission was achieved in the terbinafine and griseofulvin groups, lasting up to 8 weeks after cessation of therapy 4.
- However, in a randomized pragmatic trial, the effectiveness of terbinafine was limited, with a cure rate of 28% at 8 weeks, compared to 66% for itraconazole 6.
Treatment Recommendations
- Terbinafine is considered a first-line treatment option, along with itraconazole, in cutaneous mycoses that warrant systemic treatment 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.
- The decision to use terbinafine should be based on the extent of involvement, social situation, and availability of resources such as laboratory testing and follow-up 4.