Imagine coming down with pneumonia only to learn the antibiotics won’t work. That is a real possibility in the future due to something called antimicrobial resistance, or AMR.

AMR occurs when bacteria change over time so that medications designed to treat them become less effective. As a result, infections become harder to treat, and some treatments that work today may not work as well in the future.

What’s the Difference Between Antimicrobial Resistance and Antibiotic Resistance?

Antimicrobial resistance occurs when microorganisms, such as bacteria, viruses, fungi and parasites, change over time so that medications no longer work against them.

Antibiotic resistance is one type of AMR. Although the terms are often used interchangeably, antibiotic resistance applies only to bacteria. It occurs when bacteria become resistant to antibiotics, making those medications lose effectiveness.

Resistance develops naturally as germs evolve. When bacteria are exposed to antibiotics, some die while others survive because they have traits that help them resist treatment. Those resistant bacteria can then multiply and spread. This process can happen anytime antibiotics are used, but chances increase when antibiotics are used unnecessarily or not taken as directed.

How Could Antimicrobial Resistance Affect Your Health?

When antibiotics become less effective, common infections become harder to treat.

“Infections we used to treat easily are becoming more challenging, including urinary tract infections caused by resistant E. coli and skin infections like methicillin-resistant Staphylococcus aureus (MRSA),” says Muhammad Dhanani, MD, an infectious disease specialist at Northwestern Medicine. “We’re also seeing increasing resistance in surgical site infections and sexually transmitted infections such as gonorrhea, which limits our treatment options.”

In addition to less effective antibiotics, AMR may have broader effects on public health, including:

• More complications from infections
• Longer illnesses
• More hospitalizations
• Higher healthcare costs

Drug resistance can also make medical procedures riskier, as clinicians may be limited in the medications they can use to treat infections.

“Data from a large study indicates that deaths from antibiotic-resistant infections are projected to surpass deaths from cancer by the year 2050, making resistance an urgent threat that everyone should be concerned about,” says Rishita Shah, PharmD, an antimicrobial stewardship clinical pharmacist at Northwestern Medicine.

Infections That Are Becoming Harder To Treat

While many infections can still be treated successfully, some are becoming more difficult to treat because of growing antimicrobial resistance. Examples include:

• Urinary tract infections (UTIs), such as infections caused by drug-resistant E. coli
• Pneumonia caused by drug-resistant Streptococcus pneumoniae
• Skin infections, such as MRSA
• Surgical site infections after routine procedures
• Sexually transmitted infections, such as gonorrhea
• Secondary yeast infections
• Clostridioides difficile (C. diff)

Effects on Patients

When resistance is involved, patients undergoing procedures in hospitals may face additional risks and complications.

• Patients may need IV medications instead of oral antibiotics for common infections.
• Medications with a greater risk of side effects may be needed.
• The risk of complications may be higher.

If more infections become resistant to treatment, the consequences could be severe.

“Routine infections could become difficult to treat, and procedures like surgery, chemotherapy or organ transplants could carry higher risks due to infection,” says Dr. Dhanani.

The Role of Antibiotic Overuse or Misuse

Antibiotics are designed to treat bacterial infections, not viral illnesses, such as colds, flu or most sore throats. Misusing antibiotics in cases like this relates directly to drug-resistant infections.

Antibiotic resistance can develop when:

• Antibiotics are used when they’re not needed.
• Incorrect antibiotics are used.
• Antibiotics are not used for the right period of time.

“Through carefully designed clinical trials, we are learning that often shorter antibiotic courses are optimal,” says Dr. Shah. “But there are some infections that require long durations, such as heart valve infections like endocarditis, so it is very important to take antibiotics as directed.”

Antibiotic Resistance Isn’t Driven by Healthcare Alone

Antibiotic resistance is influenced by factors beyond healthcare, including:

• Antibiotic use in agriculture
• Global travel, which can spread resistant organisms
• Gaps in infection prevention

“Even appropriate and necessary antibiotic use can contribute to resistance over time, though in serious infections, the benefits outweigh the risks,” says Dr. Dhanani.

Reducing Your Risk of Resistant Infections

You can help reduce your risk of antibiotic-resistant infections by:

• Staying up to date on vaccinations. Vaccines help prevent illness and reduce the need for antibiotics.
• Practicing good hand-washing habits.
• Preparing food safely.
• Using antibiotics only when necessary.
• Taking prescribed antibiotics exactly as directed.
• Following infection-prevention recommendations when in healthcare settings, such as wearing a mask or a gown.
• Not sharing or saving antibiotic medications.

“Antibiotics are a shared resource,” says Dr. Shah. “You should use them as directed to keep them effective for everyone, for your future self and for future generations.”

Do You Really Need an Antibiotic?

Antibiotics treat infections caused by bacteria, not viruses. Using them when they’re not needed exposes the beneficial bacteria in the body to antibiotics. This can both promote resistance and disrupt your body’s microbiome, the community of microorganisms that helps keep your body healthy.

You may not need antibiotics when:

• You’re told you likely have a viral illness — such as the common cold, flu, most sore throats or sinusitis — or when symptoms are mild and improving.
• You don’t have a bacterial infection. Even if you have bacteria in your urine, it doesn’t always mean you have an infection. Symptoms such as pain or burning during urination, urinary urgency, flank pain or fever are often more important than a urine test result alone when determining if treatment is needed.

When antibiotics are prescribed, it’s important to take them exactly as directed, not skip doses, and never save or share them with others. If you’re unsure why an antibiotic was prescribed, ask your care team questions so you can understand why it’s needed and how to use it appropriately.

Reducing the Impact of Antimicrobial Resistance

Hospitals and healthcare systems are addressing antimicrobial resistance through antimicrobial stewardship programs that help ensure antibiotics are used appropriately. They are also using strong infection prevention practices to help stop the spread of resistant germs.

Other strategies being used include rapid diagnostics to help guide targeted antibiotics more quickly, as well as tracking resistance patterns to help with ongoing improvements.

New Treatments and Strategies

While new antibiotics are being developed, resistance continues to evolve, requiring a combination of approaches to slow its spread.

“New antibiotics can’t be our only solution,” says Dr. Shah. “Instead, we’re focusing on strategies like antimicrobial stewardship, rapid diagnostics, and more precise treatments to slow resistance and preserve the effectiveness of the therapies we already have.”

Is a “Post-antibiotic Era” Possible?

While antibiotics remain effective for many infections, both Dr. Shah and Dr. Dhanani emphasize that a future in which antibiotics are less effective is a real possibility.

“What gives me hope in the fight against antimicrobial resistance is the strong progress we’re making through antimicrobial stewardship efforts, improved diagnostics, and growing awareness among both clinicians and patients,” says Dr. Dhanani. “Combined with ongoing research for improving antibiotic use, these efforts are helping us better manage resistance and protect the effectiveness of antibiotics for the future.”

These antimicrobial stewards also stress that with responsible use, everyone can help to preserve antibiotic effectiveness.

“It takes all of us to advocate for responsible antibiotic use,” says Dr. Dhanani. “Every individual decision matters. Small actions, like not requesting antibiotics unnecessarily, collectively help slow resistance.”

Learn more about AMR and the work of the Antimicrobial and Diagnostic Stewardship team at Northwestern Medicine.