Antibiotic resistance is a critical public health challenge where bacteria evolve and become capable of resisting the effects of an antibiotic. A common misconception is that a person develops resistance, but in reality, it is the bacteria causing the infection that change. These resistant bacteria can then grow and multiply, causing an infection that is difficult, and sometimes even impossible, to treat. While your body cannot be resistant, the bacteria within it can become so, making it vital to recognize when a prescribed treatment is failing.
How to tell if your antibiotics aren't working
Since symptoms alone cannot tell you if an infection is resistant, observing how your body responds to the medication is key. If you have a bacterial infection and have started a new course of antibiotics, you should typically begin to feel better within 48 to 72 hours. If your symptoms are not improving or are getting worse after several days, it is a strong indicator that the bacteria are resistant to the prescribed drug.
Signs that the treatment may be failing include:
- Your fever does not decrease or worsens.
- Pain, swelling, or other localized symptoms do not improve.
- Overall symptoms like chills, fatigue, or headache persist.
- New or worsening symptoms develop, which can indicate the infection is progressing.
- The infection persists beyond the expected treatment window.
The diagnostic process: Confirmation of resistance
If a standard antibiotic treatment is not proving effective, a healthcare provider will investigate to confirm if resistance is the cause and identify a suitable alternative. The diagnostic process is crucial to avoid further treatment delays and potential complications.
Common diagnostic methods include:
- Patient History and Physical Exam: The doctor will review your medical history and ask about symptoms, medication use, and recent healthcare exposure. A physical exam can reveal visible signs of infection, such as an abscess in the case of MRSA.
- Bacterial Culture and Sensitivity Test: This is the most definitive method for diagnosing resistance. The doctor sends a sample of fluid or tissue (e.g., blood, urine, or pus) to a lab. The lab identifies the specific bacteria causing the infection and tests its susceptibility to various antibiotics. If the bacteria continue to grow despite exposure to a certain antibiotic, they are confirmed as resistant to that drug.
Resistance vs. other causes of treatment failure
It is important to understand that not every failed treatment is a result of antibiotic resistance. Other factors can interfere with the effectiveness of antibiotics.
| Feature | Antibiotic Resistance | Other Causes of Treatment Failure |
|---|---|---|
| Underlying Mechanism | Genetic changes in bacteria allow them to survive or neutralize the antibiotic. | Non-genetic factors related to the infection or host prevent the drug from working, even if bacteria are susceptible. |
| Typical Cause | Overuse or misuse of antibiotics, promoting adaptation in bacteria. | Poor antibiotic penetration (e.g., abscesses, biofilms), host immune dysfunction, or an incorrect initial diagnosis. |
| Lab Results | Culture and sensitivity test shows bacteria are 'resistant' to the prescribed drug. | Bacteria may show 'susceptible' results in lab tests but fail in a clinical setting. |
| Common Examples | MRSA, carbapenem-resistant Enterobacteriaceae (CRE). | Biofilm-associated infections common in chronic wounds or on medical devices. |
What to do if antibiotics aren't working
If you suspect resistance or if your infection is not improving, taking the right steps is essential.
- Contact your healthcare provider. Do not self-diagnose. Tell your doctor about your symptoms, the duration of treatment, and that you are not feeling better. They may need to order laboratory tests.
- Do not stop taking your medication. Unless directed by your doctor, continue your full course of antibiotics. Stopping early can leave surviving, potentially resistant bacteria to multiply and worsen the infection.
- Finish the full course of treatment. Always follow the exact directions given by your doctor and pharmacist, even if you start to feel better. This is one of the most effective ways to prevent resistance from developing.
- Avoid taking someone else's prescription. A medication that worked for someone else's infection may not be effective for your specific bacteria.
- Practice good hygiene. Prevent the spread of all bacterial infections, including resistant ones, by regularly washing your hands, practicing safe food handling, and staying home when sick.
Conclusion
While a person cannot become resistant to antibiotics, the bacteria causing an infection can, leading to prolonged illness and more severe complications. The primary sign of bacterial resistance is a lack of improvement in symptoms, or a worsening condition, after several days of treatment. Confirming this suspicion requires a doctor's reassessment, which often includes a culture and sensitivity test to find a more effective medication. By following your doctor's orders precisely and practicing proper antibiotic stewardship, you help protect both your own health and the broader community from the threat of antibiotic resistance.
The larger picture: Contributing factors
- Overuse and Misuse: The primary driver of antibiotic resistance is the excessive and inappropriate use of these drugs in both human and animal health. Prescribing antibiotics for viral infections like colds or the flu has no effect and only increases the risk of resistance.
- Poor Infection Control: Inadequate hygiene and sanitation in healthcare settings and communities can accelerate the spread of resistant bacteria.
- Travel: The global movement of people and goods means that resistant bacteria can spread quickly across borders.
- Substandard Prescribing: In some cases, healthcare providers may initially prescribe a broad-spectrum antibiotic that is ineffective against the specific pathogen, contributing to resistance.
- Lack of Access: In some regions, a lack of access to effective, affordable diagnostics and medicines complicates the appropriate use of antibiotics.
For more information on the global threat of antibiotic resistance, see the World Health Organization's fact sheet on antimicrobial resistance.
