When it comes to finishing off a full course of antibiotics, most parents have difficulty. So, when you or your child starts feeling well after having been on antibiotics for a few of days, it's difficult to remember to finish the medication that has a whole week left. If you don't finish the medication, all the bacteria causing the infection may not be killed. Then, the infection could come back in that same place or even show up somewhere else. The best way to cause bacteria to become resistant to antibiotics is to undertreat them.
Bacteria multiply very rapidly.
As they multiply, random mistakes occur in their DNA which can make them resistant to antibiotics. The best way to keep this from happening in your child when she has an infection is to give all the doses on time. This will kill the bacteria rapidly and efficiently. Then, when they multiply, you get a bunch of bacteria that no longer respond to the antibiotics. Some bacteria can make the immune system do things its not supposed to.