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How do narrow-spectrum antibiotics differ from broad-spectrum antibiotics?
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antimicrobial agent
Iodine, as in the form of Dobell's iodine solution, is an effective antimicrobial agent.
Antibiotics are categorized by their spectrum of activity, which defines the range of microorganisms they affect.1
- Narrow-spectrum antibiotics: These agents are highly specific and primarily target gram-positive bacteria, such as penicillin G.12
- Broad-spectrum antibiotics: These agents, including tetracyclines and chloramphenicol, are effective against a wider range of organisms, impacting both gram-positive and some gram-negative bacteria.13
Broad-spectrum agents are particularly useful for treating mixed infections or when there is insufficient time to conduct sensitivity tests. However, their use can alter the balance of normal microorganisms on the skin and mucosal surfaces, potentially allowing resistant organisms to multiply and cause secondary infections.24
Extended-spectrum antibiotics represent a further category, typically created through chemical modification to affect additional types of bacteria, often those that are gram-negative.1