Antibiotic Resistance

Antibiotic resistance is when bacteria change to resist antibiotics that used to effectively treat them. This makes certain bacterial infections difficult to treat. Overuse and misuse of antibiotics cause antibiotic resistance. You can help combat this global health problem by taking these drugs only when your provider says they’re necessary.

What is antibiotic resistance?

Antibiotic resistance occurs when bacteria change so that antibiotic medicines can’t kill them or stop their growth. As a result, bacterial infections become extremely difficult to treat.

Antibiotic resistance is a type of antimicrobial resistance. Fungi, parasites and viruses can also develop drug resistance.

Your body doesn’t develop antibiotic resistance — bacteria do. When antibiotic resistance happens, fewer antibiotics are effective against a particular bacterium. Other antibiotics often help, but it’s important to have as many treatment options available as possible. It’s also important to begin effective treatment as quickly as possible for serious infections. If it takes longer for providers to find a medication that will treat an antibiotic-resistant infection, the outcome can be more serious.

Antibiotic resistance is dangerous because it reduces treatment options for people who are sick. It may also delay effective treatment. As a result, you may face:

  • Increased risk of severe, extended illness or death.
  • Severe medication side effects.
  • Longer hospital stays.
  • More medical appointments.
  • Increased medical costs.

Public health experts and policymakers are working on solutions to antibiotic resistance. But there’s no easy fix, and it takes collaboration from a large number of people to make effective change. Learning about antibiotic resistance can help you take action to protect yourself, your loved ones and many others you’ll never meet.

What causes antibiotic resistance?

Bacteria naturally become resistant to medications over time. But certain factors can speed up the process, including:

  • Overuse of antibiotics. Taking antibiotics when you don’t need them contributes to antibiotic resistance. For instance, viruses cause most sore throats. Antibiotics won’t help. It’s important only to take antibiotics when your provider says they’re necessary and prescribes them.
  • Misuse of antibiotics. Bacteria take advantage of any opportunity to multiply. If you forget to take one or more antibiotic doses, stop treatment too soon or use someone else’s medicine, bacteria start reproducing. As they multiply, they can change (mutate). Mutated bacteria become increasingly resistant to medicine. Antibiotics can kill the bacteria that haven’t mutated to resist treatment, but they leave the resistant bacteria behind.
  • Spontaneous resistance. Sometimes, the genetic makeup (DNA) of a bacterium changes or mutates on its own. The antibiotic doesn’t recognize this newly changed bacterium and can’t target it the way it should. Or, the change helps the bacteria fight off the medicine’s effects.
  • Transmitted resistance. You can pass a contagious drug-resistant bacterial infection to someone else. That person now has an infection that won’t respond to an antibiotic. Usually, there’s a treatment that will work. But as time passes, the resistant bacteria may be harder to treat.

Who is most at risk for antibiotic-resistant infections?

Antibiotic-resistant infections can affect anyone. But certain groups are more at risk due to their health status or living environment. People more vulnerable to these types of dangerous infections include:

  • Babies, especially those born early.
  • Adults over age 65.
  • People experiencing homelessness or living in crowded conditions.
  • People who have compromised immune systems.
  • People who take antibiotics long term.


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Why is antibiotic resistance a problem?

Antibiotic resistance is a concern because it removes tools from the toolkit healthcare providers use to treat you when you’re sick. If certain bacteria can resist certain medications, providers need to find other medications to help you get better. And this isn’t always easy. But to fully understand why antibiotic resistance matters, it helps to learn how it affects us all on a global scale.

Antibiotic resistance is a global public health problem. That means it can affect you because it can affect everyone. But individual people don’t become resistant to antibiotics. Specific types of bacteria do.

That’s because, as we all use antibiotics to treat bacterial infections, those bacteria start to adapt. Think of a friend who likes to throw surprise parties. The first time, they could easily surprise you or someone else in your group. But after a while, you pick up on their plans and can sense when a surprise is coming. So, your friend has to work really hard to make a surprise happen — and they might not be able to at all.

It’s similar with bacteria. The more we “surprise” bacteria with an antibiotic, the more they become wise to it. They can see it coming, and they don’t like surprises. So, they find ways to dodge it (resist the antibiotic’s effects).

That doesn’t mean your body is becoming resistant to antibiotics. It means bacteria out there in the world (which may at some point affect your body) aren’t as easily tricked by antibiotics as they once were. So, healthcare providers must work harder to find other antibiotics to treat certain infections.

Which antibiotic-resistant bacteria are deadliest?

These bacteria are associated with the most deaths from antibiotic-resistant infections globally:

  • Escherichia coli (E. coli).
  • Staphylococcus aureus (S. aureus).
  • Klebsiella pneumoniae (K. pneumoniae).
  • Streptococcus pneumonia (S. pneumoniae).
  • Acinetobacter baumannii (A. baumannii).
  • Pseudomonas aeruginosa (P. aeruginosa).

What are superbugs?

Superbugs are bacteria, viruses or other germs that have adapted to the medicines that typically kill them. They grow wise to the drugs. Instead of going away, they continue multiplying and causing infections despite treatment. There’s a chance that no antibiotic will work.

Some bacterial infections with superbug status include:

How can we combat antibiotic resistance?

Healthcare providers and policymakers must do a good amount of the heavy lifting to change things on a global scale. But that doesn’t mean you’re powerless. There’s a lot you can do, too. Here are a few tips:

  • Practice good hygiene. Protecting yourself from infection can help you avoid bacterial infections that need antibiotics. The more we use antibiotics as a society, the more the problem of antibiotic resistance can grow. Handwashing is one important step you can take. Your healthcare provider can offer additional advice.
  • Only take antibiotics when you need them. Antibiotics don’t work against viral infections. But sometimes, bacterial and viral infections can have similar symptoms. So, you might think you need antibiotics when you don’t. If you’re sick, talk to your provider about the type of medication you need and why.
  • Get the vaccines your healthcare provider recommends. Currently, there aren’t vaccines for most bacteria that cause antibiotic-resistant infections. An exception is the pneumococcal vaccine. This protects you against pneumococcal disease caused by S. pneumoniae. The vaccine is crucial for many groups of people, especially children under age 2 and adults age 65 and older. Other vaccines are also important, including those (like the flu shot) that protect against viral infections. Avoiding viral infections can prevent symptoms that may prompt unnecessary antibiotics. 


How do healthcare providers treat antibiotic-resistant bacteria?

Treatment options are often limited. Providers look for a type of antibiotic, or a combination of medicines, that’ll treat your infection. For example, carbapenems are antibiotics that work well against antibiotic-resistant bacteria. Your provider gives you carbapenems (like meropenem) by injection.

Your provider will explain treatment options to you, as well as the benefits and risks. Researchers continue to look into new and better options for treating antibiotic-resistant bacteria. Meanwhile, following guidelines for proper antibiotic use can help existing medicines stay in our toolkit.

What is an antibiotic-resistant UTI?

Healthcare providers can treat most urinary tract infections (UTIs) with antibiotics. However, an antibiotic-resistant UTI is an infection in your urethra, bladder or kidneys that doesn’t clear up despite treatment with commonly used antibiotics.

E. coli bacteria cause most UTIs. Normally, antibiotics could clear up those infections. But bacteria are getting better at resisting treatment. For example, some strains of E. coli make enzymes called extended-spectrum beta-lactamases (ESBLs). These enzymes break down and destroy antibiotics. This prevents the antibiotics from working and your infection gets worse and harder to treat.

A provider might prescribe common antibiotics for a UTI without realizing the bacteria causing it are a resistant strain. You might start feeling better after a day or two of antibiotics. That’s because the antibiotic is killing some bacteria, but the resistant bacteria are still hanging on. So, you won’t fully recover with that current drug. Your provider may need to change your antibiotic if they find out you’re sick from a strain of antibiotic-resistant bacteria.

The good news is that there are some antibiotics that work for antibiotic-resistant UTIs. Your provider will tell you which medications are best for you. Be sure to follow the guidelines they give you for dosage and finish all your medication, even if you start to feel better.

A note from Cleveland Clinic

When you get sick, one of the first things you might wonder is what kind of medicine you can take to feel better. Thankfully, antibiotics are still powerful tools in the fight against many bacterial infections. They’ll improve your symptoms and lower the risk of serious complications. But as time goes on, more bacteria are developing resistance to medicines that have worked for years. This situation can be scary, but learning more about antibiotic resistance can help you protect yourself and those you love. Talk to your healthcare provider about ways to stay healthy. They can provide advice tailored to your unique medical needs.

Medically Reviewed

Last reviewed on 10/19/2023.

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