Antibiotic Treatment for Infected Ingrown Toenails
For mild to moderate infected ingrown toenails, use oral trimethoprim-sulfamethoxazole or amoxicillin-clavulanate as first-line therapy, with clindamycin reserved for penicillin-allergic patients. 1
Severity-Based Treatment Algorithm
Mild Infections
Mild infections present with local inflammation, pain, and minimal discharge without systemic symptoms 1:
- First-line oral antibiotics: Trimethoprim-sulfamethoxazole (TMP-SMZ) 1-2 double-strength tablets twice daily OR amoxicillin-clavulanate 875/125 mg twice daily 2, 1
- Penicillin allergy: Clindamycin 300-450 mg three times daily 2, 1
- Duration: 1-2 weeks of treatment 1
- The most common pathogen is Staphylococcus aureus, making these gram-positive coverage agents appropriate 1
Moderate Infections
Moderate infections show more extensive inflammation, purulent discharge, and pain limiting instrumental activities of daily living 1:
- Oral options: Trimethoprim-sulfamethoxazole, amoxicillin-clavulanate, levofloxacin, or clindamycin 1
- Duration: 2-4 weeks of treatment 1
- Monitoring: Assess clinical response within 2-5 days and consider culture-directed therapy or surgical intervention if no improvement 1
Severe Infections
Severe infections demonstrate significant inflammation extending beyond the toe, systemic symptoms, or limitation of self-care activities 1:
- Initial IV therapy required: Piperacillin-tazobactam OR levofloxacin/ciprofloxacin plus clindamycin 1
- MRSA suspected: Vancomycin 30 mg/kg/day in 2 divided doses IV 2, 1
- Polymicrobial infections including gram-negative organisms can occur in severe cases, necessitating broader coverage 1
Concurrent Local Measures
Always combine antibiotics with topical antimicrobial measures to optimize outcomes 1:
- Povidone-iodine 2% soaks 1
- Warm water soaks 1
- Topical antibiotics with corticosteroids for inflammation control 1
- Correct improper footwear that contributes to ongoing trauma 1
Critical Pitfalls to Avoid
Do not use antibiotics alone without addressing mechanical factors - the ingrown nail edge must be managed through conservative measures (cotton wisps, gutter splinting) or surgical intervention for definitive resolution 3, 4. Antibiotics treat the infection but do not resolve the underlying mechanical problem causing tissue trauma.
Do not continue the same antibiotic beyond 2-5 days without clinical improvement - obtain wound cultures and either adjust therapy based on results or proceed to surgical intervention 1. Persistent infection despite appropriate antibiotics suggests either resistant organisms or inadequate source control.
Consider MRSA coverage in patients with: prior MRSA infection, recent antibiotic exposure, or failure of initial beta-lactam therapy 2, 1. In these cases, add trimethoprim-sulfamethoxazole, clindamycin, or linezolid to the regimen 2.