Antibiotics are medications that are active against bacteria .
They have no effect against viruses. Properly used, they can help you recover from bacterial illnesses quickly and completely. Improperly used, they can both increase your risk of side effects, as well as make it less likely that antibiotics will work for you, and for all of us, in the future. Use antibiotics when your physician or nurse practitioner has prescribed them for you. Generally, antibiotics are prescribed after you have been examined.