How do you determine which antibiotic to prescribe for a given infection, and what should you do if a patient on antibiotic therapy for several days shows no clinical improvement?

Order (or repeat) a culture and antibiotic sensitivity test to identify the causative organism and its susceptibility pattern, guiding (or re-guiding) antibiotic selection
Simply double the current antibiotic dose without further testing
Switch to the strongest broad-spectrum antibiotic available without any testing
Stop all antibiotics and rely on incision and drainage alone in every case

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Correct answer: A. Order (or repeat) a culture and antibiotic sensitivity test to identify the causative organism and its susceptibility pattern, guiding (or re-guiding) antibiotic selection

Culture and sensitivity testing identifies the specific causative organism and which antibiotics it is susceptible to, guiding rational antibiotic selection from the start. If a patient fails to improve after several days on an antibiotic, the same principle applies: obtain (or repeat) culture and sensitivity testing to check for resistance or a different/resistant organism, rather than empirically escalating treatment without that information.

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How do you determine which antibiotic to prescribe for a given infection, and what should you do if a patient on antibiotic therapy for several days shows no clinical improvement?

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