What antibiotic is recommended for an ingrown toenail with signs of infection?

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 Classification and Initial Assessment

Before selecting antibiotics, classify the infection severity:

• Mild infections present with local inflammation, pain, and minimal discharge 1
• Moderate infections show more extensive inflammation, purulent discharge, and pain limiting instrumental activities of daily living 1
• Severe infections demonstrate significant inflammation extending beyond the toe, systemic symptoms, or limitation of self-care activities 1

The most common pathogen is Staphylococcus aureus, though polymicrobial infections including gram-negative organisms can occur. 1

Antibiotic Selection Algorithm

For Mild Infections:

• First-line options: Cefalexin (cephalexin) or dicloxacillin, which provide appropriate coverage for gram-positive cocci 1
• Alternative for penicillin allergy: Doxycycline 1
• Duration: 1-2 weeks 1

For Moderate Infections:

• First-line options: Oral trimethoprim-sulfamethoxazole, amoxicillin-clavulanate, levofloxacin, or clindamycin 1
• Duration: 2-4 weeks 1

For Severe Infections:

• Initial therapy: Intravenous piperacillin-tazobactam, levofloxacin or ciprofloxacin with clindamycin 1
• If MRSA suspected: Vancomycin 30 mg/kg/day in 2 divided doses IV 1
• Consider MRSA coverage in patients with prior MRSA infection, recent antibiotic exposure, or failure of initial beta-lactam therapy 1

Critical Antibiotic Stewardship Point

Avoid broad-spectrum empirical therapy for mild infections—therapy aimed solely at aerobic gram-positive cocci is sufficient for mild-to-moderate infections in patients who have not recently received antibiotics. 1

Essential Concurrent Measures

Antibiotics alone are insufficient. Combine with:

• Topical antimicrobials: Povidone-iodine 2% soaks or dilute vinegar soaks (50:50 dilution) twice daily 1
• Topical corticosteroids: Mid to high potency topical steroid ointment to reduce inflammation and edema 1, 2
• Warm water soaks: Daily soaking to promote drainage 1
• Footwear correction: Address improper footwear contributing to the problem 1

Monitoring and Follow-Up

• Reassess within 2-5 days for outpatient treatment 1
• If no improvement is seen, consider changing antibiotics based on culture results or proceeding to surgical intervention 1
• Obtain bacterial cultures if pus is present or infection is clinically suspected before starting antibiotics 2

Common Pitfalls to Avoid

Do not use prophylactic antibiotics for ingrown toenails without signs of infection—they are not routinely indicated. 2 Additionally, oral antibiotics before or after surgical procedures like phenolization do not improve outcomes. 3

If a subungual hematoma or abscess develops, partial or total nail avulsion may be required in addition to antibiotics. 2