What is the best antibiotic for cellulitis of the ear?

From the Guidelines

For cellulitis of the ear, the recommended first-line antibiotic treatment is a 5- to 6-day course of antibiotics active against streptococci, such as oral penicillin, amoxicillin, or clindamycin, as stated in the 2021 American College of Physicians guideline 1. This recommendation is based on the most recent and highest quality evidence, which suggests that a shorter course of antibiotics is effective for nonpurulent cellulitis, particularly for patients who can self-monitor and have close follow-up with primary care. Some key points to consider when treating cellulitis of the ear include:

• The use of antibiotics active against streptococci, as they are the most common causative organisms 1
• The consideration of a 5- to 6-day course of antibiotics, as recommended by the 2021 American College of Physicians guideline 1
• The importance of keeping the affected area clean and dry during treatment, and taking the full course of antibiotics even if symptoms improve
• The potential need for broader coverage with antibiotics such as ciprofloxacin in more severe cases or if the infection involves the cartilage (auricular perichondritis) 1 It's also important to note that if fever develops, the infection spreads beyond the ear, or symptoms don't improve within 48 hours of starting antibiotics, immediate medical reassessment is necessary as intravenous antibiotics or surgical drainage might be required.

From the Research

Antibiotic Treatment for Cellulitis of the Ear

• The choice of antibiotic for cellulitis, including that of the ear, depends on the suspected causative pathogen and local resistance patterns 2, 3, 4.
• For non-purulent, uncomplicated cases of cellulitis, which may include ear cellulitis, β-hemolytic streptococci or methicillin-sensitive Staphylococcus aureus are common causes, and oral antibiotics such as penicillin, amoxicillin, and cephalexin are often sufficient 4.
• However, in areas with a high prevalence of community-associated methicillin-resistant Staphylococcus aureus (MRSA), antibiotics with activity against MRSA, such as trimethoprim-sulfamethoxazole and clindamycin, may be preferred for empiric therapy 3.
• First-generation cephalosporins, like cephalexin, are commonly used for the treatment of cellulitis, including in pediatric patients 5.
• The route of administration (oral vs. intravenous) and duration of therapy should be based on the severity of the infection and the patient's ability to take oral medications, with oral antibiotics being effective for less severe cases 5, 6.

Considerations for MRSA

• For serious MRSA infections, parenteral vancomycin or teicoplanin (if the patient is vancomycin allergic) is recommended 2.
• In cases of less serious MRSA infections, such as skin and soft tissue infections, lincosamides (clindamycin, lincomycin) or cotrimoxazole may be used 2.
• Newer antibiotics like linezolid and quinupristin/dalfopristin have good antistaphylococcal activity but are reserved for patients who fail or are intolerant of conventional therapy due to their high cost 2.

Evidence Quality and Gaps

• The evidence for the optimum antibiotic treatment of cellulitis, including that of the ear, lacks consensus, and available trial data do not demonstrate the superiority of any agent 6.
• There is a need for future trials to use a standardized set of outcomes, including severity scoring, dosing, and duration of therapy, to better guide treatment decisions 6.