Antibiotics

Skip Navigation

Antibiotics are medicines used to kill bacteria that cause infections.

A doctor will choose an antibiotic to treat an illness based on:

  • Whether taking an antibiotic will reduce the length or severity of the illness.
  • Whether the person is allergic to any antibiotics.
  • How likely it is that a certain antibiotic will kill the bacteria believed to be causing the symptoms.
  • The symptoms and the severity of the illness.
  • Other medical problems that the person has.
  • The person's age. (For example, some antibiotics are not safe for children.)
  • Whether a woman is pregnant.



The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.