Terbinafine Treatment for Toenail Fungal Infections
Oral terbinafine at 250mg once daily for 12 weeks is the recommended first-line treatment for toenail fungal infections (onychomycosis), with mycological cure rates of 73-94%. 1
Treatment Regimen
Oral Terbinafine
Efficacy
Terbinafine is superior to other antifungal medications for dermatophyte infections:
- Mycological cure rates of 73-94% for toenails 1
- Significantly higher cure rates compared to itraconazole (73% vs 45.8%) 3
- Long-term studies show lower relapse rates with terbinafine compared to itraconazole (23% vs 53%) 4
Pre-Treatment Assessment
- Confirm diagnosis with mycological testing before starting treatment 2
- Obtain baseline liver function tests (ALT and AST) 1, 2
- Complete blood count recommended, especially for patients with risk factors 1
Patient Selection Considerations
Contraindications
Caution Required In:
- Patients with pre-existing liver disease
- Immunosuppressed patients
- Patients with lupus erythematosus
- Patients taking multiple medications (drug interactions)
Monitoring During Treatment
- Monitor for adverse effects, particularly:
- Liver problems (nausea, vomiting, abdominal pain, jaundice)
- Taste or smell disturbances
- Skin reactions
- Depressive symptoms 2
- Additional liver function tests during treatment for high-risk patients 1
Common Side Effects
- Headache
- Diarrhea
- Rash
- Dyspepsia
- Liver enzyme abnormalities
- Pruritus
- Taste disturbance
- Nausea
- Abdominal pain
- Flatulence 2
Important Considerations
- Terbinafine is fungicidal (kills fungi) rather than just fungistatic, which contributes to its superior efficacy 4
- Terbinafine has fewer drug interactions compared to azole antifungals, making it preferable for patients on multiple medications 1
- For Candida infections, itraconazole may be more effective than terbinafine 1
- Treatment failure may occur due to poor compliance, poor absorption, immunosuppression, dermatophyte resistance, or zero nail growth 1
Prevention of Recurrence
- Keep nails short
- Avoid sharing nail clippers
- Wear protective footwear in public areas
- Apply antifungal powders in shoes and on feet
- Wear cotton, absorbent socks
- Treat concomitant fungal infections 1
Terbinafine's superior efficacy, relatively low risk of side effects, and minimal drug interactions make it the treatment of choice for dermatophyte onychomycosis of the toenails when compared to other oral antifungals.