What is the recommended dose of Augmentin (amoxicillin and clavulanic acid) for a patient with a cat bite?

Augmentin Dosing for Cat Bites

For cat bite wounds, prescribe amoxicillin-clavulanate (Augmentin) 875/125 mg orally twice daily for 7-10 days, which is the first-line therapy recommended by the Infectious Diseases Society of America and American College of Physicians. 1, 2

Standard Dosing Regimen

• The recommended dose is 875 mg amoxicillin/125 mg clavulanic acid taken twice daily (every 12 hours) for 7-10 days. 1, 2, 3
• This dosing provides optimal coverage against Pasteurella multocida (100% susceptibility), staphylococci, streptococci, and anaerobic organisms that comprise the polymicrobial flora of cat bites. 1, 2
• Cat bite wounds typically yield an average of 5 different bacterial isolates, with approximately 60% having mixed aerobic and anaerobic bacteria, making broad-spectrum coverage essential. 2

Administration Instructions

• Augmentin should be taken at the start of a meal to minimize gastrointestinal intolerance and enhance absorption of clavulanate potassium. 3
• The tablets may be taken without regard to meals, but taking them with food is preferred. 3

When to Use This Regimen

• Prophylaxis: Deep wounds, puncture wounds, hand injuries, wounds near joints, or immunocompromised patients (10-20% infection risk). 1
• Treatment: Established infection with erythema, pain, edema, or purulent drainage. 1, 4
• High-risk wounds: Hand bites have the highest infection risk and complication rate (18% develop complications including tendosynovitis, septic arthritis, osteomyelitis). 2, 5

Treatment Duration

• Uncomplicated wounds: 7-10 days total treatment. 1, 2
• Deep tissue involvement: May require 3-5 days IV therapy followed by oral completion. 2
• Diabetic patients: Consider extending to 3-4 weeks if infection is extensive or resolving slowly. 6

Alternative Regimens for Penicillin Allergy

• Doxycycline 100 mg twice daily has excellent Pasteurella activity, though some streptococci may be resistant. 1, 6, 2
• Ciprofloxacin 500-750 mg twice daily provides good Pasteurella coverage but misses MRSA and some anaerobes. 1, 6, 2
• TMP-SMX 160-800 mg twice daily PLUS metronidazole 250-500 mg four times daily provides combined aerobic and anaerobic coverage. 1, 6

Critical Antibiotics to AVOID

• First-generation cephalosporins (cephalexin, cefazolin) have inadequate coverage against P. multocida and anaerobes. 1, 2
• Clindamycin monotherapy misses P. multocida despite good activity against staphylococci and anaerobes. 1, 6
• Penicillin alone or penicillinase-resistant penicillins (dicloxacillin, nafcillin) have poor P. multocida activity. 1, 2

When to Escalate to IV Therapy

• Ampicillin-sulbactam 1.5-3.0 g IV every 6-8 hours is first-line for hospitalized patients with systemic signs (fever, lymphangitis, significant cellulitis). 1, 2
• Piperacillin-tazobactam 3.37 g IV every 6-8 hours is an alternative for severe infections. 1, 2

Red Flags Requiring Immediate Return

• Increasing pain, redness, or swelling despite antibiotics. 1, 6
• Purulent drainage or fever/systemic symptoms. 1, 6
• Hand wounds require particularly close monitoring for septic arthritis, osteomyelitis, or tendonitis. 1, 6
• Symptoms can emerge as early as 3 hours after the bite, with P. multocida isolated in 70% of infected cat bites. 4

Additional Wound Management

• Thoroughly cleanse the wound with sterile normal saline using a 20-mL or larger syringe. 1, 6, 7
• Evaluate tetanus immunization status and update if needed. 1, 6, 8
• Assess rabies risk, especially for scratches from unknown or feral cats. 1, 6, 7
• Elevate the injured area to accelerate healing. 1, 6