Prophylactic Antibiotics for Cat Scratches
For simple cat scratches, prophylactic antibiotics are recommended only for deep wounds, wounds on hands/feet/face/near joints, or in immunocompromised patients—amoxicillin-clavulanate is the first-line agent. 1
Risk Stratification for Prophylaxis
Cat scratches carry a 10-20% infection risk (lower than actual bites at 30-50%), making selective rather than universal prophylaxis appropriate. 1
Indications for prophylactic antibiotics include: 1
- Deep puncture wounds
- Wounds on hands, feet, face, or near joints
- Immunocompromised patients
- Significant devitalized tissue
Prophylaxis is NOT routinely needed for: 1
- Superficial scratches
- Scratches on low-risk body areas in immunocompetent patients
First-Line Prophylactic Regimen
Amoxicillin-clavulanate 875/125 mg twice daily is the recommended first-line prophylactic antibiotic, providing optimal coverage against Pasteurella multocida and other common pathogens from cat scratches. 1
Alternative Regimens for Penicillin Allergy
For penicillin-allergic patients, doxycycline 100 mg twice daily is the preferred alternative with excellent Pasteurella multocida activity. 1
Other alternatives include: 1
- Fluoroquinolones: ciprofloxacin 500-750 mg twice daily or levofloxacin 750 mg daily
- Trimethoprim-sulfamethoxazole plus metronidazole (requires dual therapy for anaerobic coverage)
Critical Distinction: Prophylaxis vs. Cat Scratch Disease Treatment
This prophylaxis discussion applies to preventing wound infection from the scratch itself, NOT to treating cat scratch disease (CSD) caused by Bartonella henselae. 1, 2
If cat scratch disease develops (regional lymphadenopathy 3 weeks post-scratch): 2
- Azithromycin is first-line: 500 mg day 1, then 250 mg daily for 4 days (adults >45 kg) 2
- Alternative: doxycycline 100 mg twice daily for 10-14 days 1, 2
- Alternative: erythromycin 500 mg four times daily 2
Essential Wound Management
All cat scratches require thorough cleansing with sterile normal saline to remove superficial debris, regardless of whether antibiotics are given. 1
Deeper debridement is unnecessary unless significant devitalized tissue is present. 1
Additional Considerations
Evaluate and update tetanus immunization status. 1
Assess rabies risk for scratches from unknown or feral cats. 1
Advise patients to return if infection signs develop: increasing pain, redness, swelling, purulent drainage, or fever. 1
For hand wounds specifically, monitor closely for complications including septic arthritis, osteomyelitis, or tendonitis. 1
Common Pitfall to Avoid
Never use clindamycin as monotherapy for cat scratches—it lacks Pasteurella multocida coverage despite good activity against staphylococci, streptococci, and anaerobes. 1 If MRSA coverage is empirically needed alongside Pasteurella coverage, combine clindamycin with a fluoroquinolone or use alternative regimens. 1