What are the medications for cellulitis?

From the Guidelines

Cellulitis is typically treated with a 5- to 6-day course of antibiotics active against streptococci, such as cephalexin (500 mg four times daily), dicloxacillin (500 mg four times daily), or clindamycin (300-450 mg three times daily) 1. For mild to moderate uncomplicated cellulitis, oral antibiotics are usually sufficient.

• First-line options include cephalexin, dicloxacillin, or clindamycin for 5-10 days.
• If MRSA is suspected, appropriate options include trimethoprim-sulfamethoxazole, doxycycline, or linezolid.
• For severe infections or those unresponsive to oral therapy, intravenous antibiotics may be necessary, such as cefazolin, nafcillin, or vancomycin if MRSA is a concern. In addition to antibiotics, patients should:
• Elevate the affected area
• Apply warm compresses
• Monitor for signs of worsening infection like increasing redness, pain, fever, or red streaking from the infection site
• Use adequate pain control with acetaminophen or ibuprofen These antibiotics work by disrupting bacterial cell wall synthesis or protein production, effectively killing the bacteria causing the infection. Treatment duration may be extended beyond 10 days if the infection is slow to resolve, as recommended by the 2014 IDSA guideline 1. However, more recent guidelines, such as the 2019 National Institute for Health and Care Excellence (NICE) guideline, recommend a course of 5 to 7 days 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION The recommended dosage for ZYVOX formulations for the treatment of infections is described in Table 14. Table 14 Dosage Guidelines for ZYVOX Infection*Dosage and Route of AdministrationRecommended Duration of Treatment (consecutive days) Pediatric Patients† (Birth through 11 Years of Age)Adults and Adolescents (12 Years and Older)

• Due to the designated pathogens (see INDICATIONS AND USAGE) † Neonates <7 days: Most pre-term neonates < 7 days of age (gestational age < 34 weeks) have lower systemic linezolid clearance values and larger AUC values than many full-term neonates and older infants. These neonates should be initiated with a dosing regimen of 10 mg/kg q12h. Consideration may be given to the use of 10 mg/kg q8h regimen in neonates with a sub-optimal clinical response All neonatal patients should receive 10 mg/kg q8h by 7 days of life (see CLINICAL PHARMACOLOGY, Special Populations, Pediatric) ‡ Oral dosing using either ZYVOX Tablets or ZYVOX for Oral Suspension Complicated skin and skin structure infections10 mg/kg IV or oral‡ q8h600 mg IV or oral‡ q12h10 to 14 Community-acquired pneumonia, including concurrent bacteremia Nosocomial pneumonia Vancomycin-resistant Enterococcus faecium infections, including concurrent bacteremia10 mg/kg IV or oral‡ q8h600 mg IV or oral‡ q12h 14 to 28 Uncomplicated skin and skin structure infections<5 yrs: 10 mg/kg oral‡ q8h5–11 yrs: 10 mg/kg oral‡ q12hAdults: 400 mg oral‡ q12hAdolescents: 600 mg oral‡ q12h10 to 14 Adult patients with infection due to MRSA should be treated with ZYVOX 600 mg q12h

The medications for cellulitis are:

• Linezolid (PO): 600 mg q12h for adults with complicated skin and skin structure infections, including cellulitis, for 10 to 14 days 2.
• Doxycycline (PO): although the label does not explicitly state the dosage for cellulitis, it is a broad-spectrum antibiotic that can be used to treat various infections, including skin and skin structure infections 3.
• Dicloxacillin (PO): can be used to treat staphylococcal infections, but the label does not explicitly state the dosage for cellulitis 4.

Key points:

• The choice of antibiotic depends on the severity and suspected causative pathogens of the cellulitis.
• The duration of treatment should be determined by the treating physician based on the site and severity of the infection, and the patient's clinical response.

From the Research

Medications for Cellulitis

• The choice of antibiotic for cellulitis depends on various factors, including the severity of the infection and the presence of methicillin-resistant Staphylococcus aureus (MRSA) 5, 6, 7.
• A study published in 2013 found that the addition of trimethoprim-sulfamethoxazole to cephalexin did not improve outcomes in patients with uncomplicated cellulitis 5.
• Another study published in 2010 found that trimethoprim-sulfamethoxazole and clindamycin were more effective than cephalexin in treating cellulitis, especially in patients with MRSA infections 6.
• A decision analysis published in 2007 found that cephalexin was the most cost-effective option for outpatient treatment of cellulitis, but clindamycin became more cost-effective at high likelihoods of MRSA infection 7.
• A systematic review and meta-analysis published in 2019 found that there was no evidence to support the superiority of any one antibiotic over another, and that antibiotics with activity against MRSA did not add an advantage 8.
• Another systematic review and meta-analysis published in 2020 found that there was no evidence of difference in clinical response rates for antibiotic route or duration, and that the evidence base for antibiotic treatment decisions in cellulitis is flawed by biased comparisons and lack of data around harms of antibiotic overuse 9.

Antibiotic Options

• Cephalexin: a commonly used antibiotic for cellulitis, but may not be effective against MRSA 5, 6, 7.
• Trimethoprim-sulfamethoxazole: effective against MRSA, but may not be necessary for all patients with cellulitis 5, 6, 7.
• Clindamycin: effective against MRSA, and may be a good option for patients with severe cellulitis or those who are at high risk of MRSA infection 6, 7.

Treatment Duration and Route

• The optimal duration and route of antibiotic treatment for cellulitis are unclear, and more research is needed to determine the best approach 8, 9.
• A systematic review and meta-analysis published in 2020 found that there was no evidence of difference in clinical response rates for antibiotic route or duration 9.