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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.
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:
These illnesses usually go away by themselves. Ask your doctor what you can do to feel better.
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. These bacteria can change (mutate) so they are harder to kill. Then, 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 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 side effects such as:
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.
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:
Questions you can ask your doctor include:
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.
When your doctor prescribes an antibiotic:
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, ask your doctor if treatment can help you deal with the side effects. Some minor side effects are hard to avoid, but if they are more severe, discuss them with your doctor. Or ask your doctor if another antibiotic will work as well but not cause these effects.
Other Works ConsultedCenters for Disease Control and Prevention (2009). Antibiotic resistance questions and answers. Available online: http://www.cdc.gov/getsmart/antibiotic-use/antibiotic-resistance-faqs.html.
Current as ofJuly 30, 2018
Author: Healthwise StaffMedical Review: E. Gregory Thompson, MD - Internal MedicineBrian O'Brien, MD, FRCPC - Internal MedicineAdam Husney, MD - Family MedicineKathleen Romito, MD - Family MedicineTheresa O'Young, PharmD - Clinical PharmacyElizabeth T. Russo, MD - Internal Medicine
Current as of: July 30, 2018
Author: Healthwise Staff
Medical Review:E. Gregory Thompson, MD - Internal Medicine & Brian O'Brien, MD, FRCPC - Internal Medicine & Adam Husney, MD - Family Medicine & Kathleen Romito, MD - Family Medicine & Theresa O'Young, PharmD - Clinical Pharmacy & Elizabeth T. Russo, MD - Internal Medicine
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