What do I need to know about antibiotics?

Did you know:

  • Antibiotics are among the most commonly prescribed drugs. However, up to 50% of all the antibiotics prescribed for people are not needed nor as effective as hoped.
  • The overuse of antibiotics is the single most important factor that has led to antibiotic resistance.
  • Each year in the United States, at least 2 million people get serious infections with bacteria that are resistant to one or more of the antibiotics designed to treat those infections.
  • At least 23,000 people die each year as a direct result of these antibiotic-resistant infections. Almost 250,000 people each year need hospital care for treatment of Clostridium difficile (C. difficile) infections. This infection is very difficult to treat. The use of antibiotics was the main reason why the illness developed. At least 14,000 people die each year in the United States from C. difficile infections. Many of these infections could have been prevented.

The overuse or inappropriate use of antibiotics gives bacteria a chance to adapt. When this happens, the antibiotics no longer work as well to treat the infection – the bacteria become “resistant” to antibiotics.

What illnesses are caused by viruses and can’t be treated by antibiotics?

Viruses cause most upper respiratory infections, which include head colds, sore throats, bronchitis, and sinus infections. Viruses cannot be treated by antibiotics.

The common cold and flu (influenza) do not respond to antibiotics. Less than 10% of acute bronchitis cases are caused by bacteria. Most cases of acute ear infections also resolve without antibiotics.

Sore throats are usually caused by viruses as well. Antibiotics are not recommended unless you have strep throat. Only about 15% to 30% of sore throat cases in children and up to 10% of cases in adults are due to strep throat.

Almost all cases of acute bacterial sinusitis resolve without antibiotics.

The bottom line: Taking antibiotics for most acute upper respiratory tract infections does little or no good, and the downsides are real.

What’s making you sick: viruses or bacteria?

  • Cold/Runny Nose: Virus
    • Antibiotics needed: No
  • Bronchitis/Chest Cold (in otherwise healthy children and adults): Virus
    • Antibiotics needed: No
  • Whooping cough: Bacteria
    • Antibiotics needed: Yes
  • Flu: Virus
    • Antibiotics needed: No
  • Strep throat: Bacteria
    • Antibiotics needed: Yes
  • Sore throat (except strep): Virus
    • Antibiotics needed: No
  • Fluid in the Middle Ear (otitis media with effusion): Virus
    • Antibiotics needed: No
  • Urinary Tract Infection: Bacteria
    • Antibiotics needed: Yes

How are viruses treated?

Symptoms caused by viruses are usually treated with the over-the-counter drugs (drugs you can buy without a prescription). Some drugs reduce pain, such as acetaminophen (Tylenol®). Other drugs help make breathing easier (decongestants), and or relieve sneezing and runny nose (antihistamines). Symptoms can also be treated by gargling with salt water or drinking warm tea.

The best defense against getting the flu is to get a flu shot. The flu shot, however, does not protect against other viruses that cause other illnesses.

For some patients, a doctor may prescribe an antiviral drug, such as oseltamivir (Tamiflu®). These patients have a confirmed diagnosis of the flu and have risk factors for flu-related complications. These risk factors include:

  • Asthma
  • Chronic obstructive pulmonary disease (COPD)
  • Heart, liver or kidney disease
  • Age older than 65
  • Living in a nursing home
  • Weakened immune system due to cancer or HIV or organ transplantation – the immune system is the body’s defense system against infections

Although oseltamivir (Tamiflu®) does not “cure” the flu, it can shorten the amount of time with symptoms.

Finally, there are a few situations in which antibiotics are needed. See your healthcare provider if you have a weakened immune system due to cancer, or if you are taking steroids, have HIV, or have had an organ transplant. Also call if your symptoms worsen or last longer than 7 to 10 days.

If you think you may be getting the flu and you already have these conditions, you may be less able to fight bacterial infections should they occur.

Last reviewed by a Cleveland Clinic medical professional on 11/19/2016.


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