broad-spectrum agent

pharmacology

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June 22, 2026

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A broad-spectrum agent is effective against a wide range of organisms, such as insects or bacteria. In pharmacology, this term is most commonly associated with antibiotics that can combat various types of bacteria.12

Broad-spectrum antibiotics are particularly useful because they can treat infections when there isn't enough time to identify the specific bacteria causing the illness. However, they are ineffective against viruses.2

Examples of broad-spectrum antibiotics include tetracyclines and chloramphenicol, which affect both gram-positive and some gram-negative bacteria. While beneficial, the use of broad-spectrum agents can sometimes lead to the overgrowth of resistant microorganisms.23

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antibiotic
Categories of antibiotics
Broad-spectrum antibiotics, such as tetracyclines and chloramphenicol, affect both gram-positive and some gram-negative bacteria. An extended-spectrum antibiotic is one that, as a result of chemical modification, affects additional types of bacteria, usually those that are gram-negative. (The terms gram-positive and gram-negative are used to
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Broad-spectrum antibiotics, such as tetracyclines and chloramphenicol, affect both gram-positive and some gram-negative bacteria. An extended-spectrum antibiotic is one that, as a result of chemical modification, affects additional types of bacteria, usually those that are gram-negative. (The terms gram-positive and gram-negative are used to
Read More