What are the indications for Terbinafine (Lamisil)?

From the Guidelines

Terbinafine is indicated as the first-line treatment for dermatophyte onychomycosis, particularly for fingernail and toenail infections, due to its higher efficacy and tolerability compared to other antifungal agents. The treatment regimen typically involves oral terbinafine at a dose of 250 mg per day for 6 weeks in fingernail infections and 12–16 weeks in toenail infections 1.

Key Considerations

• Terbinafine has been shown to be more effective than itraconazole in treating dermatophyte onychomycosis, with higher complete cure rates and lower relapse rates 1.
• The medication works by inhibiting squalene epoxidase, disrupting fungal cell membrane synthesis, and is generally preferred for dermatophyte infections due to its fungicidal properties.
• Before prescribing terbinafine, liver function should be assessed as hepatotoxicity is a potential side effect, and the medication may interact with certain drugs metabolized by CYP2D6.

Treatment Outcomes

• Studies have demonstrated that terbinafine can achieve complete cure rates of 55% and mycological cure rates of 46% in patients with dermatophyte onychomycosis, compared to lower rates with itraconazole 1.
• A 5-year follow-up study also showed that terbinafine-treated patients had significantly lower rates of mycological and clinical relapse compared to itraconazole-treated patients 1.

Clinical Guidelines

• The British Association of Dermatologists' guidelines recommend terbinafine as the first-choice treatment for dermatophyte onychomycosis, unless contraindicated 1.
• The guidelines also suggest that patients should be re-evaluated 3–6 months after treatment initiation and further treatment should be given if the disease persists 1.

From the FDA Drug Label

Terbinafine tablets are an allylamine antifungal indicated for the treatment of onychomycosis of the toenail or fingernail due to dermatophytes (tinea unguium) Terbinafine tablets, USP are indicated for the treatment of onychomycosis of the toenail or fingernail due to dermatophytes (tinea unguium)

Terbinafine is indicated for the treatment of onychomycosis of the toenail or fingernail due to dermatophytes (tinea unguium) 2 2.

• The diagnosis of onychomycosis should be confirmed by laboratory testing before initiating treatment.
• Key words: onychomycosis, dermatophytes, tinea unguium.

From the Research

Indications for Terbinafine

Terbinafine is indicated for the treatment of various fungal infections, including:

• Dermatophyte infections such as onychomycosis, tinea pedis, tinea corporis/cruris, and tinea capitis 3, 4, 5, 6
• Superficial mycoses, including cutaneous candidiasis and pityriasis versicolor 3
• Tinea unguium (onychomycosis) 4, 5, 6

Specific Patient Populations

Terbinafine is also indicated for use in specific patient populations, including:

• Immunocompromised patients, such as those with HIV or diabetes, due to its relatively low potential for drug interactions 4
• Children with tinea capitis, with oral terbinafine administered in the dosage range 62.5 to 250 mg/day for 4 weeks 3

Comparison to Other Antifungal Agents

Terbinafine has been compared to other antifungal agents, including:

• Itraconazole, with terbinafine showing greater efficacy in some studies 3, 7
• Griseofulvin, with terbinafine showing greater efficacy and a shorter treatment duration 3, 5
• Topical antifungal agents, such as miconazole and naftifine, with terbinafine showing comparable or greater efficacy 3