From the Guidelines
The most effective treatment for cellulitis after a dog bite is amoxicillin-clavulanate 875/125 mg twice daily for 5-7 days, as it provides broad coverage against both aerobic and anaerobic bacteria, including Pasteurella multocida, Streptococcus, and Staphylococcus species 1. When considering treatment options, it's crucial to prioritize coverage for the common pathogens associated with dog bites. The choice of antibiotic should be based on the severity of the infection, patient allergies, and local resistance patterns.
- Key considerations for treatment include:
- Coverage for Pasteurella multocida, a common pathogen in dog bites
- Activity against Streptococcus and Staphylococcus species, including methicillin-resistant Staphylococcus aureus (MRSA) when necessary
- Anaerobic coverage, especially in deeper or more severe infections
- Patient factors such as penicillin allergy, which may necessitate alternative treatments like doxycycline or fluoroquinolones plus clindamycin 1 In addition to antibiotic therapy, proper wound care is essential and includes thorough cleaning, irrigation with sterile saline, and keeping the wound clean and covered. Elevation of the affected area and pain management with acetaminophen or ibuprofen may also be necessary. Tetanus prophylaxis should be updated if the patient's immunization status is not current. For severe infections or those not responding to oral antibiotics, intravenous antibiotics and hospitalization may be required, especially if there are signs of systemic infection or significant tissue involvement 1.
From the FDA Drug Label
For the treatment of skin and skin structure infections, the recommended total daily dose is 50 to 75 mg/kg given once a day (or in equally divided doses twice a day). The usual adult daily dose is 1 to 2 grams given once a day (or in equally divided doses twice a day) depending on the type and severity of infection.
The recommended treatment for cellulitis after a dog bite is ceftriaxone at a dose of:
- 50 to 75 mg/kg per day for pediatric patients, given once a day (or in equally divided doses twice a day)
- 1 to 2 grams per day for adult patients, given once a day (or in equally divided doses twice a day) The duration of therapy is typically 4 to 14 days, but may be longer in complicated infections 2.
From the Research
Causes of Cellulitis after Dog Bites
- Cellulitis after dog bites can be caused by various bacteria, including Pasteurella multocida 3, Alcaligenes faecalis 4, and Streptococcus canis 5.
- These bacteria can enter the wound through the dog's saliva or other contaminants.
Symptoms of Cellulitis after Dog Bites
- The typical clinical manifestation is a rapidly developing cellulitis at the site of injury, which can be accompanied by lymphangitis and serosanguineous or purulent drainage 3.
- Symptoms can develop within 12 to 72 hours after the dog bite 3.
Treatment of Cellulitis after Dog Bites
- Immediate surgical drainage and penicillin therapy is the treatment of choice for cellulitis caused by Pasteurella multocida 3.
- Alternative oral agents, such as amoxicillin/clavulanate, cefprozil, and ciprofloxacin, may also be effective against P. multocida infections 6.
- In cases where the patient is allergic to penicillin, other antibiotics such as coamoxicillin may be used 7.
- Hospitalization and intravenous antibiotics may be necessary in severe cases, such as those involving Alcaligenes faecalis 4.