What antibiotics are recommended to prevent wound infections?

Antibiotics for Wound Infection Prevention

For most simple, uncomplicated wounds, systemic antibiotics are not recommended—topical antibiotics and proper wound care (irrigation and debridement) are sufficient. 1

When Systemic Antibiotics ARE Indicated for Prophylaxis

Systemic antibiotic prophylaxis is recommended for:

• High-risk bite wounds (cat bites, human bites, deep puncture wounds, wounds involving hands/face/genitals, immunocompromised patients) 2
• Contaminated or potentially contaminated surgical procedures (vaginal hysterectomy, cholecystectomy in high-risk patients, open-heart surgery, prosthetic arthroplasty) 3
• Patients with systemic signs of infection, compromised immune status, severe comorbidities, or deep wounds 2
• Damaged skin (burns, pressure ulcers) when systemic signs present 2

Recommended Antibiotic Regimens by Wound Type

Animal Bites

Amoxicillin-clavulanate 875/125 mg PO twice daily is the first-line choice for prophylaxis and treatment 2, 4

• IV alternative: Ampicillin-sulbactam 1.5-3.0 g every 6 hours 2, 4
• For β-lactam allergy: Moxifloxacin 400 mg daily (covers aerobes and anaerobes as monotherapy) OR Levofloxacin 750 mg daily plus metronidazole 500 mg three times daily 2
• These regimens cover Pasteurella multocida, staphylococci, streptococci, and anaerobes 2

Human Bites

Amoxicillin-clavulanate or ampicillin-sulbactam at same doses as animal bites 2, 4

• Covers Eikenella corrodens (resistant to first-generation cephalosporins, macrolides, clindamycin), staphylococci, streptococci, and anaerobes 2
• Alternative for β-lactam allergy: Moxifloxacin as monotherapy OR fluoroquinolone plus metronidazole 2

Surgical Prophylaxis (Clean-Contaminated Procedures)

Cefazolin 1-2 g IV as single dose within 60 minutes before incision 3, 5

• For procedures involving lower GI tract or genitourinary tract where anaerobic coverage needed: Cefoxitin 1 g IV every 6-8 hours OR ceftriaxone 1 g IV plus metronidazole 500 mg IV 2, 4
• Prophylaxis should be discontinued within 24 hours post-procedure for most surgeries 3
• For high-risk procedures (open-heart surgery, prosthetic arthroplasty): may continue 3-5 days 3

Mild Skin and Soft Tissue Infections

Amoxicillin-clavulanate is first-line 4

• Alternatives: Cephalexin 500 mg four times daily or cloxacillin 4
• If MRSA suspected: Sulfamethoxazole-trimethoprim 160-800 mg twice daily 2, 4

Moderate to Severe Skin and Soft Tissue Infections

Piperacillin-tazobactam or ampicillin-sulbactam IV for broad coverage 4, 6

• Alternative: Ceftriaxone 1 g IV every 12 hours plus metronidazole 500 mg every 8 hours 2, 4, 6
• If MRSA suspected: add vancomycin, linezolid, or daptomycin 4
• If Pseudomonas risk: piperacillin-tazobactam, ceftazidime, cefepime, or carbapenems 4

Diabetic Wound Infections

For moderate to severe infections: Levofloxacin 750 mg daily, ceftriaxone, moxifloxacin 400 mg daily, ampicillin-sulbactam, or ertapenem 4

• Clinically uninfected diabetic wounds require NO antibiotics 4

Critical Timing and Duration Principles

Timing: Prophylactic antibiotics must be administered within 60 minutes before surgical incision or immediately after bite injury presentation 3, 5

• Starting earlier is unnecessary and potentially harmful; starting later is less effective 5

Duration:

• Single-dose prophylaxis is sufficient for most surgical procedures 5
• For established wound infections with adequate source control: ≤24 hours to 5-7 days maximum 4
• Prolonged courses increase resistance risk without additional benefit 4, 6

Essential Non-Antibiotic Measures

Wound irrigation and surgical debridement are MORE important than antibiotics and can substantially decrease infection incidence 2, 1

• Antibiotics are NOT a substitute for proper local wound care 1
• Deep irrigation removes foreign bodies and pathogens 2
• High-pressure irrigation should be avoided as it spreads bacteria into deeper tissues 2

Tetanus prophylaxis: Administer tetanus toxoid if >10 years since last dose for clean wounds, >5 years for dirty wounds 2

• Tdap preferred over Td if not previously given 2

Critical Pitfalls to Avoid

• Do NOT close bite wounds primarily (except facial wounds, which require copious irrigation, cautious debridement, and preemptive antibiotics) 2
• Do NOT use first-generation cephalosporins for human bites—they miss Eikenella corrodens 2
• Do NOT extend prophylaxis beyond 24 hours for routine surgical procedures 3, 5
• Do NOT use antibiotics for simple, uncomplicated wounds—topical agents suffice 1
• Avoid fluoroquinolones in elderly due to tendinopathy, CNS effects, and QT prolongation risks 4
• Cultures should be obtained before starting antibiotics when treating established infections 2, 6