What is the proper treatment for a dog bite?

Treatment for Dog Bite Wounds

Immediately irrigate the wound thoroughly with soap and water, administer amoxicillin-clavulanate for antibiotic prophylaxis (especially for high-risk wounds), update tetanus immunization if needed, and assess rabies risk with appropriate observation or prophylaxis. 1, 2

Immediate Wound Management

Wound cleansing is the single most critical intervention to prevent both infection and rabies transmission. 2

• Perform immediate and thorough washing with soap and water, followed by copious irrigation using sterile normal saline through a 20-mL or larger syringe or 20-gauge catheter to generate adequate pressure. 1, 3
• Consider adding a virucidal agent such as povidone-iodine solution to the irrigation. 2
• Explore the wound for tendon or bone involvement, periosteal penetration, and foreign bodies—pain disproportionate to injury near a bone or joint suggests deeper penetration. 2, 3
• Debride devitalized tissue carefully. 1

Wound Closure Decisions

Most dog bite wounds should NOT be closed primarily, with facial wounds being the important exception. 1

• Facial wounds: May receive primary closure after thorough irrigation and debridement for optimal cosmetic outcomes. 1
• Non-facial wounds: Should generally be left open or approximated (not fully closed) to reduce infection risk, as approximately 60% of dog bites yield mixed aerobic and anaerobic bacteria. 1, 2
• Hand wounds: Require special caution—these carry higher infection risk and should typically not be closed. 1, 2
• Heavily contaminated wounds or those presenting >8 hours after injury should not be closed. 1

Antibiotic Prophylaxis

Amoxicillin-clavulanate is the first-line antibiotic for dog bite wounds. 2, 1

Indications for Prophylactic Antibiotics (3-5 days):

• Immunocompromised, asplenic, or advanced liver disease patients 1, 4
• Hand injuries 1
• Moderate to severe injuries or wounds with tissue crush 1
• Wounds potentially penetrating periosteum or joint capsule 4
• Edema of the affected area 4
• Puncture wounds 3
• Presentation >8 hours after injury 2

Antibiotic Selection:

Oral options:

• Preferred: Amoxicillin-clavulanate (covers Pasteurella multocida found in 50% of dog bites, plus staphylococci, streptococci, and anaerobes) 2, 1
• Alternatives: Doxycycline, or fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin) plus metronidazole or clindamycin for anaerobic coverage 2, 4

Intravenous options (for severe infections):

• Ampicillin-sulbactam, piperacillin-tazobactam, second-generation cephalosporins (cefoxitin), or carbapenems (ertapenem, imipenem, meropenem) 2, 4

Antibiotics to AVOID:

Do not use first-generation cephalosporins (cephalexin), penicillinase-resistant penicillins (dicloxacillin), macrolides (erythromycin), or clindamycin alone—these have poor activity against P. multocida. 2, 1

Tetanus Prophylaxis

• Administer tetanus toxoid if the patient has not been vaccinated within the past 10 years. 1, 4
• Prefer Tdap over Td if the patient has not previously received Tdap. 4

Rabies Risk Assessment and Prophylaxis

The approach to rabies depends on whether the dog can be observed. 2

For Healthy Domestic Dogs:

• Confine and observe the dog for 10 days without starting rabies prophylaxis. 2, 4
• Monitor daily for any illness—if signs suggestive of rabies develop, euthanize the animal and submit the head for laboratory examination. 2
• Do not administer rabies vaccine to the dog during the observation period. 4

For Stray, Unwanted, or Unobservable Dogs:

• The dog should be euthanized immediately and the head submitted for rabies examination. 2
• Initiate rabies post-exposure prophylaxis (PEP) immediately if the dog cannot be observed or if in a rabies-endemic area. 2

Rabies PEP Regimen (for previously unvaccinated persons):

• One dose of rabies immunoglobulin (RIG) at presentation 2
• Rabies vaccine on days 0,3,7, and 14 2, 3
• Rabies PEP should be given regardless of delay, as incubation periods exceeding 1 year have been documented. 2, 4

Special Considerations:

• Consult local health officials to determine rabies risk in your geographic area. 1, 4
• Exposures to dogs outside the United States (especially in Asia, Africa, Central and South America) carry higher rabies risk, as dogs are the major vector in these regions. 2

Follow-up Care

• All patients must be seen within 48-72 hours to assess for signs of infection (erythema, warmth, purulent drainage, lymphangitis) and evaluate wound healing. 1, 4
• Elevate the injured body part, especially if swollen, to accelerate healing. 2

Potential Complications to Monitor

Infectious complications:

• Cellulitis, abscess formation, septic arthritis, osteomyelitis, tendonitis, and rarely bacteremia or sepsis (especially with Capnocytophaga canimorsus in asplenic or liver disease patients) 2, 4

Non-infectious complications:

• Nerve or tendon injury, compartment syndrome, post-traumatic arthritis, scarring 4

Common Pitfalls to Avoid

• Do not close non-facial wounds primarily, especially hand wounds—this significantly increases infection risk. 1
• Do not use first-generation cephalosporins or penicillinase-resistant penicillins alone for prophylaxis due to poor P. multocida coverage. 2, 1
• Do not delay rabies assessment—even if presentation is delayed by months, prophylaxis remains indicated if exposure occurred. 2
• Do not forget to report the bite—most states require physicians to report animal bites by law. 3