What antibiotic is recommended for an infected toenail (onychomycosis) following trauma?

Treatment of Infected Toenail Following Trauma

Terbinafine is the first-line oral antifungal treatment for infected toenails (onychomycosis) following trauma, with a recommended dosage of 250 mg daily for 12-16 weeks for toenail infections. 1

First-Line Treatment Options

Oral Therapy

• Terbinafine: 250 mg daily for 12-16 weeks for toenail infections; preferred over other options due to higher efficacy and lower relapse rates 1
• Itraconazole: Alternative first-line treatment at 200 mg daily for 12 weeks continuously, or as pulse therapy at 400 mg daily for 1 week per month for 3 pulses (toenails) 1

Comparative Efficacy

• Terbinafine demonstrates superior efficacy compared to itraconazole for dermatophyte onychomycosis, with higher mycological cure rates and lower relapse rates 1
• Long-term studies show mycological cure without second therapeutic intervention in 46% of terbinafine-treated patients versus only 13% of itraconazole-treated patients 1
• Relapse rates are significantly lower with terbinafine (23%) compared to itraconazole (53%) 1

Second-Line Options

• Fluconazole: 150-450 mg weekly for at least 6 months for toenail infections; useful alternative if terbinafine or itraconazole cannot be tolerated 1
• Griseofulvin: 500-1000 mg daily for 12-18 months in toenail infection; less preferred due to lower efficacy, higher relapse rates, and longer treatment duration 1

Topical Options

• Generally less effective than oral therapy for toenail infections 2
• May be considered for mild cases or when systemic therapy is contraindicated:
  • Amorolfine: 5% lacquer applied once or twice weekly for 6-12 months 1
  • Ciclopirox: 8% lacquer applied once daily for up to 48 weeks 1
  • Tioconazole: 28% solution applied twice daily for 6-12 months 1

Monitoring and Precautions

• For terbinafine: Baseline liver function tests and complete blood count recommended, especially in patients with history of hepatotoxicity or hematological abnormalities 1
• For itraconazole: Monitor hepatic function in patients with pre-existing liver issues, those on continuous therapy for more than a month, or with concomitant hepatotoxic drugs 1
• For fluconazole: Perform baseline liver function tests and monitor during high-dose or prolonged therapy 1

Prevention of Recurrence

• Keep nails short and clean 1
• Avoid walking barefoot in public places 3
• Apply antifungal powders in shoes 1
• Wear cotton, absorbent socks 1
• Consider disinfecting or discarding old footwear 1
• Treat all infected family members simultaneously 1

Common Pitfalls

• Failure to confirm diagnosis before initiating treatment 1, 3
• Inadequate treatment duration leading to recurrence 1
• Not addressing predisposing factors like continued trauma to the nail 1
• Overlooking drug interactions, particularly with terbinafine and medications like tricyclic antidepressants, SSRIs, and beta blockers 3
• Treating with topical agents alone when systemic therapy is indicated for moderate to severe infections 2