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You feel miserable. Work is piling up. You want to feel better. Your health care provider wants you to feel better. Do you need an antibiotic? It depends. If you're confused, you're not alone. Read on to understand more about using (and not using) antibiotics.

Antibiotics can be an essential part of your recovery from a bacterial illness; but they do not work against viruses.

  • Talk with your health care provider about whether you need an antibiotic.
  • Understand the potential side effects of any antibiotic you take.
  • Take the full dose of a prescribed antibiotic as instructed by your health care provider. 
  • Learn about other strategies for your comfort and recovery when antibiotics won't help.

What are antibiotics?

Antibiotics are strong medicines that can stop some infections and save lives. But antibiotics can cause more harm than good when they aren't used the right way. You can protect yourself by understanding when it is appropriate to use antibiotics and when you should avoid them.

Do antibiotics work against all infections?

No. Antibiotics only work against infections caused by bacteria (including strep throat, most ear and sinus infections, and other bacterial infections). They don't work at all against infections caused by viruses. Viruses cause colds, influenza, most mild coughs and sore throats, and other infections.

As many as half of outpatient antibiotic prescriptions written every year are unnecessary, according to the Centers for Disease Control and Prevention.

How do I know when I need antibiotics?

The answer depends on what is causing your infection. Talk with a health care provider about your symptoms, the duration of your illness, and any changes you have noticed.

The following are some basic guidelines:

  • Colds and flu — These illnesses are caused by viruses. They can't be cured with antibiotics.
  • Cough or bronchitis — These are almost always caused by viruses. However, if you have a lung condition or the illness lasts a long time, your infection may be caused by bacteria. Your clinician may decide to try treatment with an antibiotic.
  • Sore throat — Most sore throats, particularly those associated with runny nose and cough, are caused by viruses and can't be cured by antibiotics. Strep throat is caused by bacteria and requires treatment with antibiotics. A throat swab will determine whether you need an antibiotic for a sore throat.
  • Ear infections — There are several types of ear infections. Antibiotics are used for most, but not all, ear infections.
  • Sinus infections — Even if you have a runny nose, or yellow or green mucus coming from your nose, you may not need an antibiotic. Antibiotics should only be used for severe infections or infections that last more than two weeks, since these may be caused by bacteria.

What can I do to help myself?

Don't expect antibiotics to cure every illness. Don't take antibiotics for colds or flu. Often, the best thing you can do is to let colds and flu run their course.

Take care of yourself. Allow your body to heal: slow down, rest, drink plenty of fluids. Use over-the-counter medications, as appropriate, to relieve symptoms. They will not, however, speed your recovery. Talk with a nurse if you need suggestions or have questions or concerns.

Sometimes a bacterial illness can develop as a secondary infection to a viral illness. Antibiotics could become important to your recovery, even if they were inappropriate early on in your illness.

Call Gannett:

  • if you're not getting better
  • if your illness gets worse
  • if you develop more serious symptoms such as a rising fever over 101.5; acute sore throat, along with swollen glands in your neck; severe headache, neck stiffness; persistent vomiting; rash; or changes in consciousness.
  • if you think you have the flu and have been sick for less than 48 hours. Influenza will resolve without treatment, but antiviral therapy may shorten the duration of symptoms.

Talk with your health care provider....

If your provider prescribes antibiotics, you should ask:

  • What is this particular antibiotic supposed to do?
  • Is this drug likely to cause any side effects?
  • Is there anything I can do to prevent these side effects?
  • Should I take the drug at a specific time? With or without food?
  • How much does it cost?
  • Does this drug interfere with the effectiveness of other medication? (e.g., birth control pills)
  • Do I need to avoid alcohol or other foods?

Also, be sure to tell your health care provider about any:

  • previous adverse drug reactions
  • special diet
  • allergies
  • health problems
  • chance of pregnancy

How safe are antibiotics?

Antibiotics are generally safe and should always be taken as prescribed by your doctor. Antibiotics may alter the effectiveness of other medications (including the birth control pill) and cause side effects (such as stomach upsets, diarrhea, vaginal infections) or allergic reactions. Be sure to discuss known allergies and current medications with your health care provider.

Pregnant women should be aware that, as with other medications, some antibiotics may cross the placenta and cause harm.

What is the proper dosage?

Prescriptions are written for the duration required by your body to fight the harmful bacteria. When given antibiotics, take them exactly as prescribed and complete the full course of treatment. If you stop your antibiotic early, the bacteria that have not yet been killed can restart an infection. Leftover antibiotics are not a complete course, and they will not work to kill all your disease-causing bacteria. Taking partial courses can make the bacteria in your body resistant.

What is antibiotic resistance?

Taking antibiotics inappropriately can lead to antibiotic resistance, a potentially dangerous situation in which infection-causing bacteria become immune to the effects of certain antibiotics. This leaves your health care provider with fewer, often more expensive, drug options when serious bacterial infections strike in the future. A few kinds of resistant bacteria are untreatable.

Factors that contribute to antibiotic resistance include:

  • misuse and overuse of antibiotics
  • demand for antibiotics when antibiotics are not called for
  • failure to finish an antibiotic prescription


Family Doctor — search for a specific health topic; browse for health information

Alliance for the Prudent Use of Antibiotics — a non-profit, international organization solely dedicated to preserving the power of antibiotics