Topic Overview

What are antibiotics?

Antibiotics are medicines that kill bacteria. Bacteria can cause infections such as strep throat, ear infections, urinary tract infections, and sinus infections (sinusitis).

There are many types of antibiotics. Each works a little differently and acts on different types of bacteria. Your doctor will decide which antibiotic will work best for your infection.

Don't antibiotics cure everything?

Antibiotics are powerful medicines, but they cannot cure everything. Antibiotics do not work against illnesses that are caused by a virus. They do not help illnesses such as:

• Common colds.
• Influenza (flu).
• Most cases of acute bronchitis.
• Most sore throats not caused by strep.
• Runny noses.

These illnesses usually go away by themselves. Ask your doctor what you can do to feel better.

Why not take antibiotics just in case?

If you take antibiotics when you do not need them, they may not work when you do need them. Each time you take antibiotics, you are more likely to have some bacteria that the medicine does not kill. Over time these bacteria change (mutate) and become harder to kill. The antibiotics that used to kill them no longer work. These bacteria are called antibiotic-resistant bacteria.

These tougher bacteria can cause longer and more serious infections. To treat them you may need different, stronger antibiotics that cost more. A stronger antibiotic may have more side effects than the first medicine.

Antibiotic-resistant bacteria also can spread to family members, children, and fellow workers. Your community then will have a risk of getting an infection that is harder to cure and costs more to treat. Some antibiotics that doctors prescribed in the past to treat common infections no longer work.

Taking antibiotics you do not need will not help you feel better, cure your illness, or keep others from catching your infection. But taking them may cause harmful side effects. Common side effects include:

• Nausea.
• Diarrhea.
• Stomach pain.

Antibiotics also can cause Clostridium difficile colitis (also called C. difficile colitis), a swelling and irritation of the large intestine, or colon. This happens because the antibiotics kill the normal bacteria in your intestine and allow the C. difficile bacteria to grow. This problem can cause diarrhea, fever, and belly cramps. In rare cases, it can cause death.

Women may get vaginal yeast infections from taking antibiotics. In rare cases, antibiotics can cause a dangerous allergic reaction that requires emergency care.

How can I help to make sure that antibiotics are the best treatment for me?

Be smart about using antibiotics. Know that antibiotics can help treat infections caused by bacteria but not by viruses. Here are some things you can do to help make sure antibiotics will work when you need them:

• Always ask your doctor if antibiotics are the best treatment. Explain that you do not want antibiotics unless you need them.
• Avoid pressuring your doctor into prescribing antibiotics when they won't help you feel better or cure your illness. Ask your doctor what else you can do to feel better.
• Do not use antibiotics that were prescribed for a different illness or for someone else. You may delay correct treatment and become sicker.
• Protect yourself from illnesses. Keep your hands clean by washing them well with soap and clean, running water.
• Get a flu vaccine and other vaccines when you need them.

Questions you can ask your doctor include:

• Why do I need antibiotics?
• What are the side effects of this antibiotic?
• Can I do anything to prevent the side effects?
• How do I take the antibiotic? Do I take it at a certain time of day? Do I take it with food?
• Will the antibiotic interfere with any other medicines?
• Will anything happen if I take this with other medicines, certain foods, or alcohol?
• Do I need to refrigerate antibiotics? Are there any special storage instructions?

If you need to take antibiotics, always tell your doctor or pharmacist about other medicines or dietary supplements you are taking. Be sure to talk about any special diet you may be following, any food or drug allergies you may have, and any health problems you have. And make sure your doctor knows if you are pregnant or trying to get pregnant.

How do I take antibiotics?

When your doctor prescribes an antibiotic:

• Take it exactly as directed. Always take the exact amount that the label says to take. If the label says to take the medicine at a certain time, follow these directions.
• Take it for as long as prescribed. You might feel better after you take it for a few days. But it is important to keep taking the antibiotic as directed. You need the full prescription to get rid of those bacteria that are a bit stronger and survive the first few days of treatment. Bacteria that an antibiotic cannot kill (antibiotic-resistant bacteria) can develop if you (and many other people) take only part of an antibiotic prescription.

Antibiotics generally are safe. But it is important to watch for side effects. Common side effects include nausea, diarrhea, and stomach pain. In women, antibiotics can lead to vaginal yeast infections.

In rare cases, antibiotics can cause a dangerous allergic reaction that requires emergency care. If the antibiotic causes side effects that really bother you, call your doctor to ask if there is another antibiotic that will work as well but not cause these effects. Or ask your doctor if you need treatment to deal with the side effects. Some minor side effects are hard to avoid, but if they are more severe, discuss them with your doctor.