Review Question - QID 210613

A 33-year-old man presents to the emergency department with joint pain. He states that since yesterday he has had joint pain, and today he noticed a rash. The patient does not have a significant past medical history. The patient smokes cigars, drinks 1 to 4 drinks per day, is sexually active, and uses cocaine occasionally. His temperature is 101°F (38.3°C), blood pressure is 125/65 mmHg, pulse is 80/min, respirations are 14/min, and oxygen saturation is 98% on room air. A physical exam reveals pustular skin lesions and an inflamed and painful right knee that is warm to the touch. Which of the following is the most appropriate treatment for the most likely diagnosis?