The development of antibiotics was one of the greatest discoveries in modern medicine. They fight bacteria and can cure life-threatening infectious diseases such as pneumonia, for which there was previously no effective treatment. But the widespread and improper use of antibiotics means that more and more bacteria are becoming resistant to this kind of medication. So it is especially important to use them correctly.
Antibiotics can save lives, relieve the symptoms of bacterial infections and help us to recover faster. But treatment with antibiotics also has side effects. Nausea or diarrhea are common, for example.
Antibiotics are also used far too often, and improper use is fairly widespread. This has caused many different types of bacteria to become resistant (unresponsive) to antibiotics. Because resistance has become more common, many diseases can no longer be treated as well as they could in the past.
When using antibiotics, it's important to know the following things to prevent resistance and side effects:
Antibiotics only fight bacteria. Many infections are caused by viruses and can't be treated using antibiotics – examples include respiratory illnesses such as a cough, stuffy nose, bronchitis or the flu.
Excessive and improper use of antibiotics causes side effects, and in the long term reduces their effectiveness.
What is antibiotic resistance?
In medicine, bacteria and other germs are said to be resistant if they aren't affected by things that would usually be expected to harm them. An example: Most germs that enter the stomach with food will be killed by stomach (gastric) acid. But some bacteria are covered with a mucous coating that protects them from the acid. They are resistant to gastric acid.
Resistance to antibiotics works in a similar way: The bacteria have acquired a new property that protects them from the antibiotic. Some types of bacteria can produce a substance that makes certain antibiotics ineffective, for example. Bacteria that can protect themselves from several different antibiotics are referred to as "multidrug-resistant."
What causes resistance?
Many of the bacteria that are now resistant used to be killed by antibiotics. The medications could originally "disarm" certain types of bacteria and then effectively stop the infection. But the genetic material of bacteria can change by chance over time, sometimes creating new properties. For instance, a certain type of bacteria may develop properties that protect it against antibiotics. Those bacteria are then resistant to those antibiotics. These kinds of properties can also be transferred from one type of bacteria to another.
If antibiotics are used very often, resistant bacteria are better able to reproduce because the other non-resistant strains of bacteria are stopped. Then the antibiotics no longer help to fight infections caused by the resistant bacteria.
Which bacteria are resistant and why are they dangerous?
Antibiotic-resistant bacteria are often a type known as Streptococcus and Staphylococcus bacteria. One example is called “methicillin-resistant Staphylococcus aureus” (MRSA). Staphylococcus bacteria can be found on skin and mucous membranes and may cause infection – for example if they get into open wounds.
Resistant strains have now developed in other types of bacteria, such as Escherichia coli, Klebsiella and Pseudomonas bacteria.
What is being done about antibiotic resistance?
In Germany, antibiotics are prescription-only. This means that doctors are first and foremost responsible for careful and appropriate use. They should first see whether someone actually has a bacterial infection. If they do, then it's important that the antibiotic is prescribed at the right dose and for long enough, and that the right antibiotic is selected that will most effectively fight the bacteria.
There are also hygiene regulations to keep resistant bacteria from spreading further and to stop preventable infections from occurring. These measures are especially important in hospitals. Antibiotics are used there quite frequently, so resistant germs can quickly develop. To protect yourself from these germs and prevent them from spreading, you can wear disposable gloves, a medical mask that covers your nose and mouth, and a gown. Using hand sanitizers also helps. This is especially important if you come into contact with someone who is infected with resistant bacteria.
Vets and farmers use antibiotics too. So vets also have to comply with the rules for handling antibiotics sensibly.
What can I do to prevent antibiotic resistance?
Being cautious about taking antibiotics can help prevent both antibiotic resistance and side effects.
The most important thing is to not overestimate what antibiotics can do: Patients often expect to be prescribed antibiotics even though antibiotics won't help to treat their medical problem.
Antibiotics are needed to treat serious bacterial infections like lung infections or meningitis (inflammation of the membranes lining the brain and spinal cord). This is not the case when, for example, people who are otherwise healthy have respiratory infections caused by viruses, such as a cold or influenza (“the flu”). Antibiotics will usually be of no help here because they only fight bacteria. Antibiotics also have side effects such as allergic reactions, stomach and bowel problems, nausea and fungal infections. Because of these associated risks, it's important to carefully consider the advantages and disadvantages of taking antibiotics.
What's important to consider when taking antibiotics?
Antibiotics should be taken for as long as the doctor has prescribed them. Just because the symptoms of the illness go away, it doesn't mean that all of the germs have been killed. Remaining bacteria may cause the illness to start up again.
If some tablets are left over, they shouldn't be kept for later use or given to other people. Leftover medication can be thrown away in the normal waste bin or dropped off at some pharmacies. Pharmacies don't have to accept opened medicine, though. It is important not to get rid of medication by pouring it down the drain or flushing it down the toilet. That's bad for the environment and also increases the likelihood that bacteria will become resistant.
Medications can only work properly if they are used correctly. It is important to know the following things when taking antibiotics:
Can the tablets be broken into smaller pieces to make them easier to swallow? That depends on the specific medication. Doing this might stop some antibiotics from working properly.
What food can you take antibiotics with? Antibiotics are usually taken with water because taking them together with fruit juices, dairy products or alcohol can affect how the body absorbs some of them. Dairy products include milk, butter, yogurt, and cheese. After taking an antibiotic you may need to wait for up to three hours before eating or drinking any dairy products. Grapefruit juice and dietary supplements containing minerals like calcium may also lessen the effect of antibiotics.
When should you take antibiotics? Some antibiotics are always meant to be taken at the same time of day, others are meant to be taken before, with or after a meal. If you're supposed to take the medicine three times a day, for example, it usually needs to be taken at set times so that the effect is spread out evenly over the course of the day. An antibiotic that needs to be taken every 8 hours could be taken at 6 a.m., 2 p.m. and 10 p.m.
Can you take antibiotics together with other medications? Because antibiotics can interact with other medications, it's important to tell your doctor if you take other medications too. Antibiotics might interact with some blood thinners and antacids (heartburn medicine), for example. Some antibiotics can make birth control pills less effective.
You can find detailed information on how to use a specific antibiotic in the package insert. If you're not sure how to take it properly, you can ask your doctor or pharmacist.
Sources
Bundesministerium für Gesundheit (BMG), Bundesministerium für Ernährung und Landwirtschaft (BMEL), Bundesministerium für Bildung und Forschung (BMBF). DART 2020. Zwischenbericht anlässlich der WHA 2016. 2016.
Centers for Disease Control and Prevention (CDC). Antibiotic / Antimicrobial Resistance (AR / AMR). 2020.
Deutsche Gesellschaft für Infektiologie (DGI). S3-Leitlinie: Strategien zur Sicherung rationaler Antibiotika-Anwendung im Krankenhaus - Update 2018. AWMF-Register-Nr.: 092-001. 2019.
Kayser FH, Böttger EC, Deplazes P et al. Taschenlehrbuch Medizinische Mikrobiologie. Stuttgart: Thieme; 2014.
World Health Organization (WHO). Antimicrobial resistance. 2020.
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