A cat scratch might seem minor at first, but if the area becomes red, swollen, warm, or painful, you could be developing cellulitis—a potentially serious bacterial skin infection. Prompt, appropriate antibiotic treatment is crucial to prevent the infection from spreading. Here’s what you need to know about cellulitis after a cat scratch, which antibiotics doctors usually prescribe, alternatives for those with allergies, and how to heal safely.
What Is Cellulitis?
Cellulitis is an infection of the deeper layers of the skin and underlying tissue. It can occur when bacteria—most commonly Pasteurella multocida (found in cat mouths), Staphylococcus aureus, or Streptococcus species—enter through a scratch, bite, or wound. Cat scratches and bites are higher risk than most animal injuries due to the unique bacteria cats carry.
- Symptoms: Redness, swelling, warmth, pain, and tenderness around the wound. Fever, chills, and red streaks are signs the infection is spreading.
- Onset: Symptoms often start within hours to a few days after the injury.
Why Cat Scratches Are High Risk for Cellulitis
Cats have sharp claws and carry Pasteurella multocida, a bacterium that can cause skin infections more rapidly and severely than those from dogs or other animals. Scratches can inoculate this bacteria deep under the skin, making cellulitis more likely.
First-Line Antibiotic: Amoxicillin-Clavulanate (Augmentin)
The **most widely recommended first-line oral antibiotic for cellulitis from a cat scratch in adults and children is**:
- Amoxicillin-clavulanate (brand name: Augmentin)
- Effective against Pasteurella, Staph, Strep, and anaerobic bacteria commonly introduced by cat scratches.
- Usually taken twice daily for 7–10 days (duration and dose depend on severity and individual factors).
- Most people notice improvement in redness, swelling, and pain within 24–48 hours, but you must finish the full course.
Alternatives for Penicillin or Amoxicillin Allergies
If you are allergic to penicillins or cannot take Augmentin, your doctor may recommend:
- Doxycycline (often paired with metronidazole or clindamycin)
- Clindamycin plus a fluoroquinolone (like ciprofloxacin) or trimethoprim-sulfamethoxazole (TMP-SMX)
- Azithromycin or clarithromycin (less commonly used, but may be appropriate for certain patients)
Your doctor will choose the safest and most effective combination based on your medical history and the severity of your infection.
When to See a Doctor
- If redness, swelling, or pain spreads or worsens after a cat scratch
- If you develop a fever, chills, or feel unwell
- If you see red streaks moving away from the wound
- If the area feels very warm or you notice pus or drainage
- If you have a weakened immune system, diabetes, or are elderly—cellulitis can progress more rapidly and require urgent care
What to Do While Waiting for Treatment
- Clean the area gently with soap and water
- Apply a sterile bandage
- Elevate the affected area if possible to reduce swelling
- Avoid squeezing, picking, or applying creams/ointments without medical advice
How to Prevent Cellulitis from Cat Scratches
- Trim your cat’s claws regularly
- Avoid rough play with cats using your hands
- Clean any scratch or bite immediately with soap and water
- Keep cats indoors and discourage contact with stray animals
- Supervise children with cats and teach gentle handling
Frequently Asked Questions
Is Neosporin or topical antibiotic enough?
No. Topical antibiotics can help prevent minor surface infections, but true cellulitis is a deep tissue infection that requires oral (or intravenous) antibiotics.
How soon should antibiotics be started?
Antibiotics should be started as soon as cellulitis is diagnosed. Early treatment reduces risk of complications and speeds healing.
What happens if cellulitis isn’t treated?
Untreated cellulitis can lead to abscess, bloodstream infection (sepsis), or spread to joints and bones—potentially requiring hospitalization.
Do I need a tetanus or rabies shot after a cat scratch?
If your tetanus vaccination is not current, a booster may be recommended. Rabies from domestic cats is very rare, but see a doctor promptly if the cat is stray or unvaccinated.
What about “cat scratch disease” (Bartonella)?
Cat scratch disease is caused by a different bacteria (Bartonella henselae) and usually causes swollen lymph nodes, not cellulitis. Some antibiotics (like doxycycline) can treat both. Your doctor will advise the best option for your symptoms.
Conclusion: Early, Proper Antibiotic Treatment Is Key
Cellulitis from a cat scratch is a medical issue that requires timely, evidence-based care. **Amoxicillin-clavulanate (Augmentin)** is the preferred first-line oral antibiotic. Alternatives exist for those with allergies, but always follow your doctor’s advice and finish the full prescription. Prompt action and follow-up can prevent complications and help you recover quickly and safely.