What is the treatment for cellulitis?

From the Guidelines

Cellulitis should be treated with antibiotics active against streptococci, with a recommended duration of 5 days, as stated in the 2014 update by the Infectious Diseases Society of America 1. The choice of antibiotic depends on the severity of the infection and patient factors. For mild cases, oral antibiotics such as penicillin, amoxicillin, amoxicillin-clavulanate, dicloxacillin, cephalexin, or clindamycin are suitable options 1.

• Key considerations in treating cellulitis include:
  • Elevation of the affected area to reduce swelling
  • Taking over-the-counter pain relievers like acetaminophen or ibuprofen as needed
  • Keeping the area clean and dry
  • Completing the full course of antibiotics even if symptoms improve quickly
  • Seeking immediate medical attention if symptoms worsen or if the patient develops fever, increasing pain, numbness, or if the redness spreads rapidly In more severe cases, intravenous antibiotics such as cefazolin or vancomycin may be necessary, especially if MRSA is suspected 1.
• It is essential to note that the treatment should be tailored to the individual patient's needs, and the duration of therapy may need to be extended if the infection has not improved within the initial 5-day period 1. Proper hydration, rest, and elevation of the affected area support the body's natural healing processes and can help reduce the risk of complications, such as lymphedema, which can occur with severe or repeated episodes of cellulitis 1.

From the FDA Drug Label

The cure rates in clinically evaluable patients with complicated skin and skin structure infections were 90% in linezolid-treated patients and 85% in oxacillin-treated patients The cure rates by pathogen for microbiologically evaluable patients are presented in Table 18. Table 18 Cure Rates at the Test-of-Cure Visit for Microbiologically Evaluable Adult Patients with Complicated Skin and Skin Structure Infections Pathogen Cured ZYVOX n/N (%) Oxacillin/Dicloxacillin n/N (%) Staphylococcus aureus 73/83 (88) 72/84 (86) Methicillin-resistant S aureus 2/3 (67) 0/0 (-) Streptococcus agalactiae 6/6 (100) 3/6 (50) Streptococcus pyogenes 18/26 (69) 21/28 (75)

The recommended dosage for linezolid formulations for the treatment of complicated skin and skin structure infections is 600 mg IV or oral every 12 hours 2.

• Cellulitis treatment can be achieved with linezolid, with cure rates of 90% in clinically evaluable patients 2.
• The cure rates for Staphylococcus aureus and Methicillin-resistant S aureus were 88% and 67% respectively 2.
• Linezolid is effective against Gram-positive pathogens, including MRSA 2.
• The dosage for adult patients with infection due to MRSA is 600 mg q12h 2.

From the Research

Cellulitis Treatment Overview

• Cellulitis is a common skin infection that can be challenging to distinguish from other conditions, with no gold standard diagnostic test available 3.
• The treatment of cellulitis typically involves antibiotic therapy, with the selection of antibiotics determined by patient history, risk factors, severity of clinical presentation, and the most likely microbial culprit 3.

Antibiotic Route and Duration of Therapy

• There is uncertainty about the benefit of intravenous (IV) over oral (PO) antibiotic therapy for cellulitis, as well as the appropriate duration of treatment 4.
• Studies have found that IV antibiotic therapy is often preferred in patients with more severe cellulitis or those who have received antibiotics prior to trial entry 4.
• However, research has also shown that patients who receive only PO therapy may be more likely to improve at day 5 compared to those who receive at least a single dose of IV therapy, with no significant difference in outcomes at day 10 and day 30 4.
• A systematic review and meta-analysis found that there is no evidence to support the superiority of any one antibiotic over another, and that antibiotics with activity against methicillin-resistant Staphylococcus aureus do not add an advantage 5.

Efficacy and Safety of Antibiotics

• A network meta-analysis of randomized controlled trials found that there are no significant differences in cure rates among antibiotics for cellulitis, although ceftriaxone had the fewest gastrointestinal side effects 6.
• The same study found that pristinamycin showed the highest cure rates for erysipelas, but with a higher risk of rash 6.
• Overall, the evidence suggests that the choice of antibiotic and route of administration should be individualized based on patient factors and the severity of the infection, rather than a one-size-fits-all approach 4, 5, 6.