Treatment of Onychomycosis
The first-line treatment for onychomycosis is oral terbinafine 250mg once daily for 12 weeks for toenail infections and 6 weeks for fingernail infections, as it has the highest efficacy with 70-80% mycological cure rates. 1, 2
Diagnosis Confirmation
Before initiating treatment:
- Laboratory confirmation is essential via:
This confirmation is crucial as only approximately half of nail dystrophies are fungal in origin. 1
Treatment Algorithm
First-line therapy:
- Oral terbinafine 250mg daily
Second-line options:
- Itraconazole 200mg daily for 12 weeks (45.8% mycological cure rate) 1
- Fluconazole 150-450mg once weekly for at least 6 months (useful alternative when terbinafine or itraconazole cannot be tolerated) 1
Topical options (for mild cases or when oral therapy is contraindicated):
- Amorolfine 5% nail lacquer (50% efficacy in distal nail infections)
- Ciclopirox 8% lacquer (34% mycological cure rate)
- Efinaconazole 10% solution (50% mycological cure rate)
- Tioconazole 28% solution (contraindicated in pregnancy) 1
Special Populations
Pediatric patients:
- Terbinafine dosing based on weight:
- 62.5 mg/day for children under 20 kg
- 125 mg/day for children between 20-40 kg
- 250 mg/day for children over 40 kg 1
Patients with HIV or immunosuppression:
- Terbinafine and fluconazole preferred due to lower risk of interactions with antiretrovirals 1
Diabetic patients:
- Terbinafine preferred due to lower risk of drug interactions
- Consider topical treatments for mild-to-moderate infections when risk of drug interaction is high 1
Monitoring and Follow-up
Patients should be advised to report immediately any symptoms of:
- Persistent nausea, anorexia, fatigue, vomiting
- Right upper abdominal pain, jaundice, dark urine or pale stools
- Taste or smell disturbances
- Depressive symptoms
- Skin reactions (hives, mouth sores, blistering, peeling) 2
Treatment should be discontinued if these adverse effects occur 2
Prevention of Recurrence
Recurrence occurs in 40-70% of cases. Preventive measures include:
- Maintaining short and clean nails
- Drying feet well after bathing
- Wearing cotton socks and changing them daily
- Applying antifungal powders to shoes and feet
- Avoiding sharing nail clippers
- Wearing protective footwear in public areas
- Treating concomitant fungal infections promptly 1
Common Pitfalls
- Not confirming diagnosis before treatment - This can lead to ineffective therapy and increased recurrence risk 1
- Inadequate treatment duration - Results in incomplete cure and higher recurrence rates 1
- Simultaneous use of corticosteroids with antifungals - Can compromise treatment efficacy 1
- Unrealistic expectations about improvement speed - Can lead to patient dissatisfaction and non-adherence 1
- Not addressing predisposing factors - Such as concomitant tinea pedis 1
Management of Treatment Failure
If treatment fails, consider:
- Partial nail removal plus antifungal therapy
- Alternative antifungal drug
- Complete nail avulsion combined with antifungal therapy 1
Reasons for treatment failure include poor compliance, poor absorption, immunosuppression, dermatophyte resistance, subungual dermatophytoma, and zero nail growth. 1