Which statement best describes the effect of broad-spectrum antibiotics on resistance risk?

Which statement best describes the effect of broad-spectrum antibiotics on resistance risk?

• A. Broad-spectrum antibiotics can disrupt normal flora, increasing resistance.
• B. Broad-spectrum antibiotics have no effect on resistance.
• C. Narrow-spectrum antibiotics cause more resistance.
• D. All antibiotics are equally likely to cause resistance.

Answer: (A)

When thinking about resistance risk, it’s about how antibiotics disturb the microbial environment inside us. Broad-spectrum antibiotics attack a wide range of bacteria, not just the pathogen. This broad hit knocks out many members of the normal flora that normally help keep harmful organisms in check. With these beneficial competitors reduced, resistant bacteria can thrive and spread, and resistance genes can transfer more easily among bacteria. That ecological disruption increases the overall risk of resistance developing. That’s why the statement about broad-spectrum antibiotics disrupting normal flora and raising resistance risk is the best fit. The other ideas miss the core point: resistance isn’t a zero-sum, universal outcome, and using targeted (narrow-spectrum) therapy generally causes less disruption and less selective pressure than broad-spectrum use.

When thinking about resistance risk, it’s about how antibiotics disturb the microbial environment inside us. Broad-spectrum antibiotics attack a wide range of bacteria, not just the pathogen. This broad hit knocks out many members of the normal flora that normally help keep harmful organisms in check. With these beneficial competitors reduced, resistant bacteria can thrive and spread, and resistance genes can transfer more easily among bacteria. That ecological disruption increases the overall risk of resistance developing.

That’s why the statement about broad-spectrum antibiotics disrupting normal flora and raising resistance risk is the best fit. The other ideas miss the core point: resistance isn’t a zero-sum, universal outcome, and using targeted (narrow-spectrum) therapy generally causes less disruption and less selective pressure than broad-spectrum use.