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When to Use Antibiotics  

Antibiotics are medicines used to treat infections caused by bacteria. They don’t work for an illness caused by a virus. And they don't work for an allergic reaction. In fact, taking antibiotics for reasons other than an infection by bacteria can cause problems. You may have side effects from the medicine. And if you need an antibiotic in the future, it may not work well. This is because the bacteria can become immune to the medicine. You can also get a type of diarrhea that's hard to treat. This diarrhea is called C. diff. 

When antibiotics likely won’t help

Your healthcare provider won’t usually give you antibiotics for the conditions listed below. You can help by not asking for them if you have: 

  • A cold. This type of illness is caused by a virus. It can cause a runny nose, stuffed-up nose, sneezing, coughing, and headache. You may also have mild body aches and low fever. A cold gets better on its own in a few days to a week.

  • The flu (influenza). This is a respiratory illness caused by a virus. The flu usually goes away on its own in a week or so. It can cause fever, body aches, sore throat, and tiredness.

  • Bronchitis. This is an infection in the lungs. It is most often caused by a virus. You may have coughing, phlegm, body aches, and a low fever. A common type of bronchitis is known as a chest cold. This is called acute bronchitis. This often happens after you have a respiratory infection like a cold. Bronchitis can take weeks to go away. Antibiotics often don’t help.

  • Most sore throats. Sore throats are most often caused by viruses. Your throat may feel scratchy or achy. It may hurt to swallow. You may also have a low fever and body aches. A sore throat usually gets better in a few days.

  • Most outer ear infections. An ear infection may be caused by a virus or bacteria. It causes pain in the ear. Antibiotics by mouth usually don’t help. Low-dose antibiotic ear drops work much better.

  • Some inner ear infections. An inner ear infection (otitis media) can be caused by a virus in the ear. It can also cause pain and a high fever. Most older children with low-grade fever don't need to be treated with antibiotics.

  • Most sinus infections. This is also known as sinusitis. This kind of infection causes sinus pain and swelling, and a runny nose. In most cases, it goes away on its own. Antibiotics don’t make recovery quicker.

  • Allergic rhinitis. This is a set of symptoms caused by an allergic reaction. You may have sneezing, a runny nose, itchy or watery eyes, or a sore throat. Allergies are not treated with antibiotics.

  • Low fever. A mild fever that’s less than 100.4°F (38°C) most likely doesn’t need to be treated with antibiotics. 

When antibiotics can help

Antibiotics can be used to treat:                                                   

  • Strep throat. This is a throat infection caused by a certain type of bacteria. Symptoms of strep throat include a sore throat, white patches on the tonsils, red spots on the roof of the mouth, fever, body aches, and nausea and vomiting. Strep throat almost never causes a cough.

  • Urinary tract infection (UTI). This is an infection of the bladder and the tube that takes urine out of the body. It is caused by bacteria. It can cause burning pain and urine that’s cloudy or tinted with blood. UTIs are very common. Antibiotics usually help treat them.

  • Some outer ear infections. In some cases, a healthcare provider may prescribe antibiotics by mouth for an ear infection. You may need a test to show the cause of the ear infection.

  • Some sinus infections. In some cases, your healthcare provider may give you antibiotics. He or she may first need to make sure your symptoms aren’t caused by something else. This may be a virus, fungus, allergies, or air pollutants such as smoke. 

Your healthcare provider may give you antibiotics if you have a condition that can affect your immune system. This includes diabetes or cancer.

Self-care at home

If your infection can’t be treated with antibiotics, you can take other steps to feel better. Try the remedies below. In general: 

  • Rest and sleep as much as needed.

  • Drink water and other clear fluids.

  • Don’t smoke. Stay away from smoke from other people.

  • Use over-the-counter medicine such as acetaminophen or ibuprofen to ease pain or fever, as directed by your healthcare provider.

To treat sinus pain or nasal stuffiness:

  • Put a warm, moist cloth on your face where you feel sinus pain or pressure.

  • Try a nasal spray with medicine or saline. Use as directed by your healthcare provider.

  • Breathe in steam from a hot shower.

  • Use a humidifier or cool mist vaporizer. 

To quiet a cough: 

  • Use a humidifier or cool mist vaporizer.

  • Breathe in steam from a hot shower.

  • Suck on cough lozenges. 

To sooth a sore throat: 

  • Suck on ice chips, frozen ice pops, or lozenges.

  • Use a sore throat spray.

  • Use a humidifier or cool mist vaporizer.

  • Gargle with saltwater.

  • Drink warm liquids.

  • Take ibuprofen to reduce swelling and pain.

To ease ear pain: 

  • Hold a warm, moist washcloth on the ear for 10 minutes at a time.

Online Medical Reviewer: Eric Perez MD
Online Medical Reviewer: Paula Goode RN BSN MSN
Online Medical Reviewer: Raymond Kent Turley BSN MSN RN
Date Last Reviewed: 12/1/2019
© 2000-2020 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.