Terbinafine Treatment for Onychomycosis

Dosing Recommendations

• The British Association of Dermatologists recommends 250 mg of terbinafine daily for 12-16 weeks for toenail infections 1
• Patients should be re-evaluated 3-6 months after treatment initiation, and further treatment should be given if the disease persists 1, 2

Evidence Supporting This Recommendation

• Terbinafine is considered first-line treatment for dermatophyte onychomycosis due to its superior efficacy and tolerability compared to other antifungals 1
• Terbinafine is fungicidal against dermatophytes with very low minimum inhibitory concentrations 3, 4

Comparative Efficacy

• Terbinafine has demonstrated higher efficacy than itraconazole in dermatophyte onychomycosis 1

Monitoring and Safety Considerations

• Baseline liver function tests (LFTs) are recommended before starting treatment 4, 2
• More vigilant LFT monitoring is advised in patients with pre-existing liver disease, concomitant hepatotoxic medications, continuous therapy for more than one month, or history of heavy alcohol consumption 2
• Terbinafine is contraindicated in patients with active or chronic liver disease, history of allergic reaction to oral terbinafine, or lupus erythematosus 4

Common Side Effects and Drug Interactions

• Terbinafine has minimal drug interactions compared to azole antifungals 2
• The main interaction concern is with drugs metabolized by cytochrome P450 2D6 isoenzyme 2