Immediate Management of Rat Bites
Immediately wash the wound thoroughly with copious amounts of soap and water, then irrigate with large volumes of water or saline—this is the single most important initial step to prevent both bacterial infection and rabies. 1
Initial Wound Care (First 15 Minutes)
- Irrigate the wound extensively with large amounts of water or saline to remove pathogens and reduce infection risk 1
- Wash thoroughly with soap and water, as this alone has been shown in animal studies to markedly reduce rabies transmission 1
- Consider adding a virucidal agent such as povidone-iodine solution to the irrigation 1
- Avoid high-pressure irrigation, as this may drive bacteria deeper into tissue 1
What NOT to Drink
The question about "what to drink" appears to be a misunderstanding—there is no oral medication or beverage that provides protection after a rat bite. All treatment is topical wound care, injectable prophylaxis (rabies/tetanus), and oral/IV antibiotics if indicated.
Risk Assessment and Wound Classification
Rat bites can be categorized into three types that guide treatment 2:
- Type I: Superficial scratches—require only conservative wound care
- Type II: Deeper bites with potential infection/ulceration—may need debridement
- Type III: Full-thickness tissue loss—requires surgical intervention and possible skin grafting
Most rat bite wounds show minimal inflammation and do not require hospital admission 2
Antibiotic Prophylaxis Decision
Universal antibiotic prophylaxis is NOT recommended for all rat bites 1. Consider antibiotics only for:
- Deep wounds or puncture wounds 1, 3
- Wounds on hands, feet, joints, face, or genitals 1
- Wounds presenting within 24 hours that are "dirty" or contaminated 1, 3
- Patients with immunocompromise or implants 1
Do NOT give antibiotics if the patient presents ≥24 hours after the bite without signs of infection 1
Antibiotic Selection (If Indicated)
- First-line oral: Amoxicillin-clavulanate 4
- Penicillin allergy alternatives: Doxycycline, or fluoroquinolone (ciprofloxacin/levofloxacin/moxifloxacin) plus metronidazole or clindamycin 4
- Duration: 3-5 days for prophylaxis 1
Rat bites can transmit Streptobacillus moniliformis causing rat bite fever, which presents with fever, rash, and polyarthritis 5, 6, 7
Rabies and Tetanus Prophylaxis
Rabies Risk from Rats
Rabies prophylaxis is generally NOT indicated for rat bites in the United States, as rodents (including rats) are rarely infected with rabies and have not been known to transmit rabies to humans 1. However:
- If rabies exposure is suspected in exceptional circumstances, previously unvaccinated persons should receive both rabies immune globulin (RIG) and vaccine 4
- RIG dose: 20 IU/kg body weight, infiltrated around the wound with remainder given intramuscularly 1
- Vaccine schedule: Days 0,3,7,14, and 28 4
Tetanus
- Administer tetanus toxoid (0.5 mL IM) if vaccination status is outdated or unknown 4
Wound Closure
- Do NOT close infected wounds 4
- For clean wounds seen early (<8 hours), consider Steri-Strips rather than sutures 4
- Most rat bites should be managed with conservative wound care without closure 2
Follow-Up
- Arrange follow-up within 24 hours (phone or office visit) for outpatients 4
- Monitor for signs of infection or rat bite fever (fever, rash, joint pain developing days to weeks later) 5, 6
- Hospitalize if infection progresses despite appropriate antibiotics 4
Common Pitfalls
- Over-prescribing antibiotics for superficial wounds that only need wound care 1, 2
- Unnecessary rabies prophylaxis—rats are not significant rabies vectors 1
- Closing wounds prematurely, increasing infection risk 4
- Missing rat bite fever diagnosis when fever is absent—maintain high suspicion with rash and arthritis 5