Antimicrobial spectrum

The antimicrobial spectrum of an antibiotic means the range of microorganisms it can kill or inhibit.

Nonetheless, the range of microorganisms which an antibiotic can kill or inhibit in vivo may not always be the same as the antimicrobial spectrum based on data collected in vitro.

[2][5] Narrow-spectrum antibiotics have low propensity to induce bacterial resistance and are less likely to disrupt the microbiome (normal microflora).

[3] On the other hand, indiscriminate use of broad-spectrum antibiotics may not only induce the development of bacterial resistance and promote the emergency of multidrug-resistant organisms, but also cause off-target effects due to dysbiosis.

[2][8] The Healthcare Infection Control Practices Advisory Committee (HICPAC) recommends the use of narrow-spectrum antibiotics whenever possible.

A simplified diagram showing common disease-causing bacteria and the antibiotics which act against them.