Abscesses are sometimes treated with a procedure and an oral antibiotic regimen that covers MRSA (eg, trimethoprim 160 mg / sulfamethoxazole 800 mg once or twice a day OR trimethoprim 160 mg / sulfamethoxazole 800 mg once or twice a day PLUS amoxicillin-clavulanate 875 mg twice a day OR trimethoprim 160 mg / sulfamethoxazole 800 mg once or twice a day PLUS metronidazole 500 mg 3 times a day).