You can also view previously answered questions in the HSW Question Archive . When you are fighting off a bacterial infection, your immune system can be overwhelmed by the invading bugs. Antibiotics are thrown into the fray to mount a defense against the invaders until your immune system can recover and finish off the remaining bacteria.
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. Another strategy is to create the molecular equivalent of a club bouncer to escort antibiotics out the door if it gets in. Some bacteria use energy from ATP to power pumps that shoot antibiotics out of the cell. Changing the target Many antibiotics work by sticking to their target and preventing it from interacting with other molecules inside the cell.