What is the first-line antibiotic choice for a cut on the hand with signs of infection?

First-Line Antibiotic for Infected Hand Laceration

For a cut on the hand with signs of infection, amoxicillin-clavulanate 875/125 mg twice daily is the first-line antibiotic choice, providing comprehensive coverage against the most common pathogens including Staphylococcus aureus, Streptococcus species, and anaerobic bacteria. 1

Rationale for Amoxicillin-Clavulanate

• Hand wounds are at high risk for polymicrobial infection involving both aerobic organisms (S. aureus, Streptococcus species) and anaerobic bacteria from skin flora and environmental contamination 1
• Amoxicillin-clavulanate provides broad-spectrum coverage that addresses all common pathogens encountered in hand wound infections, making it superior to narrow-spectrum agents 1
• The Infectious Diseases Society of America specifically recommends this agent for contaminated hand injuries due to its proven efficacy against mixed bacterial populations 1

Alternative Antibiotic Options

For Penicillin-Allergic Patients:

• Doxycycline 100 mg twice daily is the preferred alternative, offering good activity against staphylococci and some anaerobes 1
• Clindamycin is another option for penicillin-allergic patients, indicated for serious skin and soft tissue infections caused by susceptible streptococci and staphylococci 2
• Moxifloxacin 400 mg daily provides good anaerobic coverage but should be reserved due to fluoroquinolone stewardship concerns 1

For Mild, Non-Contaminated Wounds:

• Cephalexin 500 mg four times daily can be considered for simple, less contaminated wounds where anaerobic coverage is less critical 3, 4
• However, cephalexin alone lacks adequate anaerobic coverage and should not be used for heavily contaminated hand wounds 1

Treatment Duration and Monitoring

• Standard duration: 5-7 days for uncomplicated infections 1
• Extend treatment if infection has not improved within this timeframe 1
• Monitor for signs of treatment failure including worsening erythema, purulent discharge, or systemic symptoms 4

Critical Management Considerations Beyond Antibiotics

• Thorough irrigation and debridement to remove foreign material is essential and equally important as antibiotic therapy 1
• Consider imaging (ultrasound or X-ray) if foreign body retention is suspected 1
• Ensure tetanus prophylaxis is current 1
• Obtain wound cultures before starting antibiotics if possible, particularly for severe infections 1

When to Consider MRSA Coverage

Add empiric MRSA coverage (such as trimethoprim-sulfamethoxazole or doxycycline) if: 1

• Prior history of MRSA infection
• Initial treatment failure after 48-72 hours
• Severe immunocompromise present
• Systemic inflammatory response syndrome (SIRS) criteria met

Severe Infections Requiring IV Therapy

• Ampicillin-sulbactam 1.5-3.0 g IV every 6-8 hours for severe infections with systemic involvement 1
• Piperacillin-tazobactam 3.37 g IV every 6-8 hours as an alternative for severe cases 1
• Transition to oral therapy once clinical improvement is evident 1

Common Pitfalls to Avoid

• Do not use cephalexin alone for contaminated hand wounds - it lacks anaerobic coverage necessary for soil or debris contamination 1
• Do not rely solely on antibiotics - inadequate wound care (irrigation, debridement) will lead to treatment failure regardless of antibiotic choice 1
• Do not extend antibiotics beyond 7 days without reassessment - prolonged courses increase resistance risk without additional benefit 1
• Avoid beta-lactams as monotherapy if MRSA is suspected based on local epidemiology or patient risk factors 5