From the Guidelines
Uncomplicated cellulitis is best treated with a 5-day course of oral antibiotics targeting Streptococcus species, as recommended by the Infectious Diseases Society of America 1. The first-line treatment options include penicillin, amoxicillin, amoxicillin-clavulanate, dicloxacillin, cephalexin, or clindamycin, with a suitable choice depending on the patient's allergy status and local resistance patterns 1.
- Key considerations for treatment include:
- Elevation of the affected area to reduce swelling and promote healing
- Application of warm compresses to increase blood flow and reduce pain
- Marking the border of the infection with a pen to monitor progression
- Adequate pain control with acetaminophen or NSAIDs
- Patients should be advised to seek immediate medical attention if they develop fever over 101°F, increasing pain, rapid spread of redness beyond the marked border, or development of streaking redness. The recommended duration of antimicrobial therapy is 5 days, but treatment should be extended if the infection has not improved within this time period, as stated in the guidelines 1.
- It is essential to complete the full antibiotic course even if symptoms improve quickly to prevent recurrence or antibiotic resistance. In cases where MRSA is suspected, consideration should be given to using antibiotics effective against this pathogen, such as vancomycin or other suitable alternatives, as recommended in the guidelines 1.
- Outpatient therapy is recommended for patients who do not have systemic signs of infection, altered mental status, or hemodynamic instability, allowing for effective management of uncomplicated cellulitis in a non-hospital setting 1.
From the FDA Drug Label
For the following infections, a dosage of 500 mg may be administered every 12 hours: streptococcal pharyngitis, skin and skin structure infections, and uncomplicated cystitis in patients over 15 years of age. The recommended dose of cephalexin (PO) for uncomplicated cellulitis is 500 mg every 12 hours 2.
From the Research
Uncomplicated Cellulitis
- Uncomplicated cellulitis is a common skin infection that can be challenging to diagnose due to its non-specific symptoms and lack of a gold standard diagnostic test 3, 4.
- The majority of non-purulent, uncomplicated cases of cellulitis are caused by β-hemolytic streptococci or methicillin-sensitive Staphylococcus aureus, and can be treated with oral antibiotics such as penicillin, amoxicillin, and cephalexin 3.
- The use of intravenous antibiotics over oral antibiotics is not supported by evidence, and treatment duration of longer than 5 days does not result in any additional benefit 5, 6.
Antibiotic Treatment
- A combination therapeutic regimen of amoxicillin + clavulanic acid has been linked with the shortest duration of stay in the hospital for patients with erysipelas or bacterial cellulitis 7.
- There is no evidence to support the superiority of any one antibiotic over another, and antibiotics with activity against methicillin-resistant Staphylococcus aureus do not add an advantage 6.
- The choice of antibiotic should be determined by patient history and risk factors, severity of clinical presentation, and the most likely microbial culprit 4.
Diagnosis and Management
- Cellulitis is a clinical diagnosis based on the history of present illness and physical examination, and lacks a gold standard for diagnosis 3, 4.
- Thorough history and clinical examination can narrow the differential diagnosis of cellulitis and minimize unnecessary hospitalization 4.
- Patients with uncomplicated cellulitis can be treated with oral antibiotics, and the duration of treatment should be based on the severity of the infection and the patient's response to treatment 5, 6.