How do bacteria become resistant to antibiotics?

A: Bacteria can become resistant to antibiotics through several ways. Some bacteria can “neutralize” an antibiotic by changing it in a way that makes it harmless. Others have learned how to pump an antibiotic back outside of the bacteria before it can do any harm. read more

Bacteria employ similar strategies to keep antibiotics at bay. One effective way to keep a drug from reaching its target is to prevent it from being taken up at all. Bacteria do this by changing the permeability of their membranes or by reducing the number of channels available for drugs to diffuse through. read more

However, bacteria may also become resistant in two ways: 1) by a genetic mutation or 2) by acquiring resistance from another bacterium. Mutations, rare spontaneous changes of the bacteria's genetic material, are thought to occur in about one in one million to one in ten million cells. read more