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How do antibiotics work to kill bacteria?

Medically reviewed by Drugs.com. Last updated on April 1, 2024.

Official answer

by Drugs.com

Antibiotics work by interfering with the bacterial cell wall to prevent growth and replication of the bacteria. Human cells do not have cell walls, but many types of bacteria do, and so antibiotics can target bacteria without harming human cells.

Antibiotics are either bactericidal (they kill the bacteria) or bacteriostatic (they keep the bacteria from reproducing and growing).

Antibiotics have no action on viruses that are the cause of the common cold, the flu, and many coughs, so they are not effective against these types of illnesses.

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