What antibiotic is recommended for a laceration?

Antibiotic Recommendations for Lacerations

For most simple lacerations, antibiotic prophylaxis is not routinely recommended as it does not significantly reduce infection rates.

Decision Algorithm for Antibiotic Use in Lacerations

No Antibiotics Needed:

• Simple, clean lacerations with minimal contamination
• Lacerations properly irrigated and debrided
• Closed globe injuries
• Vein surgery lacerations
• Carotid surgery without patch

Antibiotics Recommended:

1. Cranio-cerebral wounds:

   • Aminopenicillin + beta-lactamase inhibitor (e.g., amoxicillin-clavulanate) 2g IV slow, then 2g every 8 hours for maximum 48 hours 1
   • If penicillin allergic: vancomycin 30 mg/kg/120 min, then 30 mg/kg/day for maximum 48 hours 1

2. Open eye trauma:

   • Levofloxacin 500 mg IV on day 1, followed by 500 mg orally on day 2 1

3. Lacrimal duct wounds:

   • Penicillin 2g with reinjection of 1g if procedure >2 hours 1

4. Limb amputation:

   • Aminopenicillin + beta-lactamase inhibitor 2g IV slow, then 1g every 6 hours for 48 hours 1
   • If allergic: clindamycin 900 mg IV slow, then 600 mg every 6 hours for 48 hours plus gentamicin 5 mg/kg/day with reinjection at 24 hours 1

5. Contaminated wounds:

   • Cephalexin 500 mg orally every 6 hours for 7 days 2
   • If penicillin allergic: clindamycin 300 mg orally every 6 hours for 7 days 2

Important Considerations

Factors that increase risk of infection:

• Heavily contaminated wounds
• Crush injuries
• Delayed presentation (>8 hours)
• Immunocompromised host
• Wounds involving joints, tendons, or bone
• Hand or foot lacerations (higher risk areas)
• Presence of foreign bodies
• Poor vascular supply

Evidence Analysis

The evidence regarding antibiotic prophylaxis for simple lacerations is mixed but generally suggests limited benefit:

• A 1983 study showed no significant difference in infection rates between patients receiving cephalexin (7.0%) versus no antibiotics (6.25%) for simple lacerations 3

• A more recent feasibility study (2014) found an extremely low infection rate of only 1% in patients with simple hand lacerations, suggesting that prophylactic antibiotics may not be necessary in most cases 2

• For uncomplicated skin wounds, proper wound cleaning, irrigation, and debridement remain the most important factors in preventing infection 4

Pitfalls to Avoid

1. Overuse of antibiotics: Prescribing antibiotics for all lacerations increases antibiotic resistance risk without clear benefit
2. Prolonged prophylaxis: Antibiotic prophylaxis should be brief, limited to the operative period, sometimes 24 hours and exceptionally to 48 hours 1
3. Neglecting proper wound care: Thorough irrigation and debridement are more important than antibiotics for preventing infection
4. Forgetting tetanus prophylaxis: Always assess tetanus immunization status in patients with lacerations

Special Situations

Hand Lacerations

Despite common practice, evidence does not strongly support routine antibiotic prophylaxis for simple hand lacerations:

• A feasibility study showed only 1% infection rate in simple hand lacerations 2
• However, hand lacerations with high contamination may benefit from prophylaxis

Bite Wounds

• Human and animal bites have higher infection risk and typically warrant antibiotic prophylaxis
• Amoxicillin-clavulanate is the preferred agent for bite wounds due to its coverage of oral flora

Remember that proper wound cleansing, irrigation, debridement, and appropriate closure technique remain the cornerstones of laceration management, with antibiotics playing a secondary role in specific high-risk situations.