Antimicrobial spectrum


The antimicrobial spectrum of an antibiotic means the range of microorganisms it can kill or inhibit. Antibiotics can be divided into broad-spectrum antibiotics, extended-spectrum antibiotics and narrow-spectrum antibiotics based on their spectrum. Detailedly, broad-spectrum antibiotics can kill or inhibit a huge range of microorganisms; extended-spectrum antibiotic can kill or inhibit Gram positive bacteria and some Gram negative bacteria; narrow-spectrum antibiotic can only kill or inhibit limited species of bacteria.
Currently no antibiotic's spectrum can completely cover all types of microorganisms.

Determination

The antimicrobial spectrum of an antibiotic can be determined by testing its antimicrobial activity against a wide range of microbes in vitro . 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.

Significances

Generally, a wider antimicrobial spectrum of an antibiotic means it can be used in more clinic indications of it.

Examples