Which of the following can be used to treat MRSA in an outpatient setting?

Bactrim, which is a combination of sulfamethoxazole and trimethoprim, is effective against Methicillin-resistant Staphylococcus aureus (MRSA) in outpatient settings. This antibiotic works by inhibiting bacterial folate synthesis, which is crucial for the growth and replication of bacteria. Bactrim has been shown to have good efficacy against various strains of MRSA, particularly in cases of uncomplicated skin and soft tissue infections.

In outpatient treatment, particularly where MRSA is suspected, Bactrim is often preferred due to its oral bioavailability and the convenience it offers for patients who do not require intravenous therapy. It is also generally well-tolerated, making it a suitable option for outpatient management of MRSA infections.

The other options do not effectively treat MRSA in an outpatient setting. Amoxicillin is not effective against MRSA due to the organism's resistance to penicillin derivatives. Metronidazole primarily targets anaerobic bacteria and protozoa and is not effective against MRSA. Ciprofloxacin, although a fluoroquinolone antibiotic, has limited activity against MRSA and is not recommended for treating it, particularly in outpatient scenarios.