What are the treatment options for cellulitis?

Treatment Options for Cellulitis

For non-purulent cellulitis, a 5- to 6-day course of antibiotics active against streptococci is recommended as first-line therapy. 1, 2

First-Line Antibiotic Selection

• Oral options for uncomplicated cellulitis include:

  • Penicillins: dicloxacillin 3, amoxicillin, amoxicillin-clavulanate 2
  • Cephalosporins: cephalexin (500 mg four times daily) 2, 4
  • Clindamycin (for penicillin-allergic patients) 1, 2

• Parenteral options for severe infections include:

  • Penicillinase-resistant penicillins: nafcillin 1
  • First-generation cephalosporins: cefazolin 1, 5
  • For life-threatening penicillin allergies: clindamycin or vancomycin 1

Duration of Therapy

• A 5-day course of antibiotics is as effective as a 10-day course for uncomplicated cellulitis if clinical improvement occurs 1, 2
• Treatment should be extended if the infection has not improved within the initial 5-day period 1, 2

When to Consider MRSA Coverage

• Standard treatment for typical non-purulent cellulitis does not require MRSA coverage 2
• Consider adding MRSA coverage only in specific situations:
  • Cellulitis associated with penetrating trauma 2
  • Evidence of MRSA infection elsewhere 2
  • Purulent drainage 2
  • History of injection drug use 1, 2
  • Systemic inflammatory response syndrome 1

Adjunctive Therapy

• Elevation of the affected area to promote drainage of edema and inflammatory substances 2
• Systemic corticosteroids may be considered in non-diabetic patients to reduce inflammation and hasten resolution 1, 2
• Nonsteroidal anti-inflammatory drugs (NSAIDs) may help reduce inflammation and speed resolution when added to antibiotic therapy 6

Hospitalization Criteria

• Consider inpatient treatment for patients with:
  • Severe infections with systemic inflammatory response syndrome 2
  • Altered mental status 2
  • Hemodynamic instability 2
  • Concern for deeper or necrotizing infection 2
  • Poor adherence to therapy 2
  • Immunocompromised status 2
  • Failure of outpatient treatment 2

Prevention of Recurrence

• For patients with frequent episodes of cellulitis, consider prophylactic antibiotics:

  • Oral penicillin 2
  • Oral erythromycin 2
  • Intramuscular benzathine penicillin 2

• Address underlying conditions that predispose to recurrence:

  • Treat tinea pedis and other toe web abnormalities 1, 2
  • Manage venous insufficiency and lymphedema 2, 7

Common Pitfalls to Avoid

• Don't extend treatment unnecessarily beyond 5 days if clinical improvement has occurred 1, 2
• Don't automatically add MRSA coverage for typical non-purulent cellulitis without specific risk factors 2, 8
• Don't forget to examine interdigital toe spaces in lower-extremity cellulitis, as treating fissuring or maceration may reduce recurrence 1, 2
• Don't overlook the importance of elevating the affected area, especially in patients with venous insufficiency or lymphedema 2
• Don't confuse cellulitis with conditions that can mimic it, such as venous insufficiency, eczema, deep vein thrombosis, and gout 7