What is the recommended antibiotic regimen for cat bite prophylaxis?

Cat Bite Prophylaxis: Antibiotic Regimen

Amoxicillin-clavulanate (875/125 mg twice daily orally) is the first-line antibiotic prophylaxis for cat bites due to its excellent coverage against Pasteurella multocida and other common bite wound pathogens. 1, 2

Rationale for Prophylaxis

Cat bites have a significantly higher infection rate (20-80%) compared to dog bites (3-18%), primarily due to:

• High prevalence (approximately 90%) of Pasteurella multocida in feline oral flora 3
• Deep puncture wounds created by cats' narrow, sharp teeth
• Higher risk of infection, especially with bites to the hands 4

First-Line Antibiotic Options

• Oral therapy (outpatient):

  • Amoxicillin-clavulanate: 875/125 mg twice daily for 5-7 days 1, 5

• Intravenous therapy (for severe infections):

  • Ampicillin-sulbactam: 1.5-3.0 g every 6-8 hours 1
  • Piperacillin-tazobactam: 3.37 g every 6-8 hours 1

Alternative Options for Penicillin-Allergic Patients

• Doxycycline: 100 mg twice daily - excellent activity against P. multocida 1

• Fluoroquinolones:

  • Ciprofloxacin: 500-750 mg twice daily
  • Levofloxacin: 750 mg daily
  • Moxifloxacin: 400 mg daily 1

• Combination therapy options:

  • Clindamycin plus fluoroquinolone
  • Metronidazole plus fluoroquinolone
  • Trimethoprim-sulfamethoxazole plus metronidazole 2

Antibiotics to Avoid

• First-generation cephalosporins (miss P. multocida)
• Clindamycin alone (misses P. multocida)
• Macrolides
• Penicillinase-resistant penicillins 2

Duration of Therapy

• Prophylaxis/uncomplicated infections: 5-7 days 5
• Established infections: 7-10 days
• Severe or complicated infections: 10-14 days 2

Special Considerations

High-Risk Wounds Requiring Prophylaxis

• All cat bites (due to high infection risk)
• Bites to the hand or over joints
• Deep puncture wounds
• Wounds in immunocompromised patients
• Wounds with significant crush injury 2

Wound Management

• Thorough cleansing with sterile saline
• Removal of debris
• Elevation of affected area
• Consider delayed primary closure for wounds >8 hours old 2

Monitoring and Follow-up

• Follow-up within 24-48 hours to assess for signs of infection
• Watch for increasing pain, erythema, swelling, or purulent drainage
• Consider hospitalization for severe infections, especially those involving the hand 2

Pitfalls to Avoid

• Underestimating the infection risk of cat bites (much higher than dog bites)
• Using antibiotics with poor activity against P. multocida
• Delayed treatment (increases risk of complications)
• Failure to consider tetanus prophylaxis when indicated
• Missing deep structure involvement (tendons, joints, bones) 6

The high susceptibility of P. multocida to amoxicillin-clavulanate (100%) confirms it remains an excellent first-line choice for prophylaxis and treatment of cat bite wounds 3.