Do Not Use Pediatric Augmentin in Cats
You should not administer pediatric Augmentin to your cat for this abscess. While amoxicillin-clavulanate can be effective for feline skin infections and abscesses, the pediatric formulations and dosing guidelines are designed for humans and are not appropriate for veterinary use.
Why This Matters
The evidence provided focuses entirely on human pediatric dosing for acute otitis media 1, 2, 3, which is fundamentally different from treating a feline abscess. A posterior ear abscess in a cat requires:
- Species-appropriate dosing: Cats metabolize drugs differently than humans, with distinct pharmacokinetic parameters
- Veterinary formulations: The clavulanate ratios in pediatric Augmentin (particularly ES-600 at 90/6.4 mg/kg/day) 3 are optimized for human pathogens and human drug metabolism
- Proper wound management: Abscesses typically require surgical drainage, debridement, and culture-guided therapy—not just oral antibiotics
What the Veterinary Evidence Shows
For feline skin wounds and abscesses, amoxicillin alone at 11-22 mg/kg (mean 13.8 mg/kg) twice daily for 7-10 days achieved 95.1% clinical success 4. The most common pathogens (Pasteurella multocida and anaerobes like Prevotella, Fusobacterium, and Porphyromonas) showed excellent in vitro susceptibility to amoxicillin alone 4.
Recent pharmacokinetic data in cats demonstrates that amoxicillin-clavulanate at 10 mg/kg amoxicillin + 2.5 mg/kg clavulanate (a 4:1 ratio) achieves therapeutic levels 5. However, oral bioavailability in cats is only 33-76% depending on formulation 5, 6, making precise dosing critical.
Critical Safety Concerns
- Clavulanate toxicity: The high clavulanate doses in pediatric formulations (6.4 mg/kg in ES-600) 3 may cause gastrointestinal upset in cats, as clavulanate is associated with diarrhea even in human children 7
- Incorrect pathogen coverage: Human respiratory pathogens (S. pneumoniae, H. influenzae) 2, 8 differ from feline abscess pathogens
- Dosing errors: A 10-pound (4.5 kg) cat would require approximately 45-90 mg amoxicillin based on veterinary data, but calculating this from pediatric suspensions risks significant over- or under-dosing
What You Must Do
Take your cat to a veterinarian immediately. The abscess likely requires:
- Surgical drainage and debridement (abscesses rarely resolve with antibiotics alone)
- Culture and sensitivity testing from the purulent material
- Veterinary-approved antibiotics at species-appropriate doses
- Pain management (abscesses are extremely painful)
If cost is a barrier, many veterinary clinics offer payment plans, and some communities have low-cost veterinary services. Attempting to treat this at home with human medications risks treatment failure, antibiotic resistance, and unnecessary suffering for your cat.
Human medications—even antibiotics—should never be used in animals without veterinary guidance, as the margin between therapeutic and toxic doses can be narrow in cats.