What condition can result from the excessive use of broad-spectrum antibiotics?

The excessive use of broad-spectrum antibiotics can lead to antibiotic resistance, which is a significant public health concern. Broad-spectrum antibiotics target a wide variety of bacteria, including both pathogenic and beneficial bacteria. When these antibiotics are used excessively or inappropriately, they can disrupt the normal microbiota, allowing resistant bacteria to thrive and proliferate.

This occurs because the non-resistant bacteria may be killed off, reducing competition and creating an environment where resistant strains can flourish. Over time, these resistant bacteria can spread, making infections harder to treat, as some strains may no longer respond to standard antibiotic therapies. This resistance can develop through mechanisms such as genetic mutations or horizontal gene transfer between bacteria, leading to the emergence of multi-drug resistant strains.

In contrast, options related to improved immune response or reduced infection rates are not direct results of excessive antibiotic use, as the depletion of useful microbiota can actually compromise the immune system and increase susceptibility to infections. Therefore, the link between broad-spectrum antibiotic overuse and the development of antibiotic resistance is a well-established concept in microbiology and infectious disease management.