Augmentin 875 mg Twice Daily for 5 Days After Dog Bite
Augmentin (amoxicillin-clavulanate) 875 mg twice daily is the correct antibiotic choice for dog bite prophylaxis, but the duration should be 3-5 days for fresh wounds, not necessarily 5 days for all presentations 1, 2.
Antibiotic Selection
Amoxicillin-clavulanate 875/125 mg twice daily is the first-line oral agent recommended by IDSA guidelines for animal bite wounds 1. This combination provides optimal coverage against:
- Pasteurella multocida (isolated in 20-30% of dog bites)
- Staphylococcus and Streptococcus species
- Anaerobes (Fusobacterium, Prevotella, Bacteroides)
- Other oral flora from the dog's mouth
The 875 mg formulation is appropriate for adults and provides adequate amoxicillin dosing while maintaining the clavulanate at 125 mg to minimize gastrointestinal side effects 3.
Duration: The Critical Nuance
The 5-day duration is appropriate for most prophylactic scenarios, but timing matters:
Fresh wounds (<9 hours old): Prophylactic antibiotics show no significant benefit in low-risk wounds 4. However, most experts still recommend 3-5 days for deep wounds or high-risk locations 2.
Wounds 9-24 hours old: Antibiotics provide significant benefit (P=0.023), and 3-5 days is recommended 4, 2.
Wounds >24 hours old without infection: Antibiotics should not be given unless clinical signs of infection are present 2.
High-Risk Features Requiring Prophylaxis
Prophylactic antibiotics for 3-5 days are indicated when:
- Hand, foot, or periarticular locations (highest infection risk)
- Face or genital area wounds
- Deep wounds involving tendons, joints, or bone
- Puncture wounds (4.1-fold increased infection risk) 5
- Wounds requiring closure (3.1-fold increased infection risk) 5
- Immunocompromised patients or those with prosthetic devices 2
Low-Risk Wounds
For superficial, non-puncture wounds on the extremities or trunk that are <12 hours old and don't require closure, the infection rate is only 2.6% 5. In these cases, prophylactic antibiotics may not be necessary 6, though wound care with irrigation and debridement remains essential.
Critical Pitfalls
Do not use Augmentin if the patient presents >24 hours post-bite without signs of infection 2—you're selecting for resistance without benefit.
Cat bites have 30-50% infection rates (vs. 5-25% for dogs) and almost always warrant prophylaxis 2.
Hand wounds are the highest risk anatomic location and should receive prophylaxis even if otherwise low-risk 4.
Puncture wounds appear deceptively minor but carry significantly higher infection risk 5.
Administration Details
Take at the start of meals to minimize GI intolerance and enhance clavulanate absorption 3. The most common side effects are diarrhea, nausea, and vomiting.
Alternative Agents
If penicillin allergy exists, alternatives include:
- Doxycycline 100 mg twice daily (excellent P. multocida coverage) 1
- Moxifloxacin 400 mg daily (monotherapy with anaerobic coverage) 1
Your 5-day course is reasonable for prophylaxis in most dog bite scenarios, particularly if the wound has any high-risk features or presents within 9-24 hours of injury.