Antibiotics – The Facts

What are antibiotics?
Antibiotics are medicines that can stop some infections and even save lives. But antibiotics can do more harm than good if they are not used correctly. Protect yourself and your family by knowing when to use antibiotics and when not to. The Centers for Disease Control and Prevention offers up-to-date information on antibiotic resistance and proper use at

Do Antibiotics work against all infections?
No. Antibiotics only work against infections caused by bacteria. They do not work against infections caused by viruses. Viruses cause colds, the flu, sinus infections, and most coughs and sore throats.

What is “antibiotic resistance”?
When bacteria are exposed to the same antibiotic again and again, the antibiotic stops working. Being exposed to the same antibiotic for a long time can make some bacteria change, become stronger so they can fight back against the antibiotics. These bacteria are said to be “resistant” to this antibiotic.

Why should I worry about antibiotic resistance?
If you take antibiotics that cannot fight bacteria they are supposed to kill, your infection might get worse. You might have to make several visits to your health care provider. You might have to take different medications or go to a hospital for stronger antibiotics, which may have to be given intravenously.

Some kinds of resistant bacteria cannot be treated. People with whom you come in contact may catch the resistant bacteria that you have. Then they could get infections that are hard to cure. Every time you take antibiotics when you do not really need them, you increase the chance that you will get an illness that is caused by bacteria that are resistant to antibiotics.
Antibiotic resistance is a growing problem in the United States. Resistant bacteria grow faster when antibiotics are used too often or are not used correctly.

How do I know if I need antibiotics?
Here are the best guidelines for antibiotic use:
• Colds and flu are caused by viruses. They cannot be cured with antibiotics.
• Cough and bronchitis are almost always caused by viruses. But if these problems do not go away, bacteria may be the cause. Then your health care provider may prescribe an antibiotic.
• Sore throats: 85% of them are caused by viruses while only 15% are caused by bacteria, the majority of which is strep. Your health care provider may do a lab test before prescribing antibiotics for strep throat.
• Coughs, bronchitis and sinusitis can be caused by viruses or bacteria. Antibiotics are sometimes used to treat sinus infections.
• A runny nose with green or yellow mucus does not always mean you need to take an antibiotic. Viruses or hydration issues can cause mucus to change color. Remember, it is important to stay hydrated when you have a cold.

How should I take the antibiotics that my health care provider prescribes?
• Follow your health care provider’s directions carefully. Take all of the medication as prescribed.
• Do not take antibiotics prescribed to anyone else.
• Tell your health care provider about all other medications you are taking including prescribed, over-the-counter, & supplements.
• Only your health care provider should decide if you need antibiotics – not your friends or your mom!