What antibiotic is commonly prescribed for cellulitis in patients who are not severely ill?

Cephalexin is a commonly prescribed antibiotic for cellulitis in patients who are not severely ill due to its efficacy against the most prevalent causative organisms, which include Streptococcus and Staphylococcus species. Cephalexin, a first-generation cephalosporin, is effective in targeting these gram-positive bacteria, and it is often chosen because it is well-tolerated and has a favorable oral bioavailability, making it suitable for outpatient treatment.

When treating uncomplicated cellulitis in outpatient settings, cephalexin provides a good balance of effectiveness while minimizing the risk of resistance and avoiding the need for intravenous administration. It allows for easier patient compliance, as it can be taken orally, and it is often well-reviewed for its safety profile.

In contrast, other options like vancomycin and linezolid are typically reserved for cases where methicillin-resistant Staphylococcus aureus (MRSA) is a concern or when treating more serious infections, which would align more with hospital admissions. Ceftriaxone, while effective for a range of infections, is more commonly used for conditions requiring broader coverage or intravenous therapy rather than uncomplicated outpatient cellulitis. Thus, cephalexin is the most appropriate choice for uncomplicated cellulitis in stable patients