Antibiotics, also known as antibacterials, are medications that destroy or slow down the growth of bacteria.
They include a range of powerful drugs and are used to treat diseases caused by bacteria.
Antibiotics cannot treat viral infections, such as cold, flu, and most coughs.
This article will explain what antibiotics are, how they work, any potential side effects, and antibiotic resistance.
Fast facts on antibiotics
- Alexander Fleming discovered penicillin, the first natural antibiotic, in 1928.
- Antibiotics cannot fight viral infections.
- Fleming predicted the rise of antibiotic resistance.
- Antibiotics either kill or slow the growth of bacteria.
- Side effects can include diarrhea, an upset stomach, and nausea.
Antibiotics are powerful medicines that fight certain infections and can save lives when used properly. They either stop bacteria from reproducing or destroy them.
Before bacteria can multiply and cause symptoms, the immune system can typically kill them. White blood cells (WBCs) attack harmful bacteria and, even if symptoms do occur, the immune system can usually cope and fight off the infection.
Sometimes, however, the number of harmful bacteria is excessive, and the immune system cannot fight them all. Antibiotics are useful in this scenario.
The first antibiotic was penicillin. Penicillin-based antibiotics, such as ampicillin, amoxicillin, and penicillin G, are still available to treat a variety of infections and have been around for a long time.
Several types of modern antibiotics are available, and they are usually only available with a prescription in most countries. Topical antibiotics are available in over-the-counter (OTC) creams and ointments.
Some medical professionals have concerns that people are overusing antibiotics. They also believe that this overuse contributes toward the growing number of bacterial infections that are becoming resistant to antibacterial medications.
According to the Centers for Disease Control (CDC), outpatient antibiotic overuse is a particular problem. Antibiotic use appears to be higher in some regionsTrusted Source, such as the Southeast.
Use of carbapenems, a major class of last-line antibiotics, increased significantly from 2007 to 2010.
There are different types of antibiotic, which work in one of two ways:
- A bactericidal antibiotic, such as penicillin, kills the bacteria. These drugs usually interfere with either the formation of the bacterial cell wall or its cell contents.
- A bacteriostatic stops bacteria from multiplying.
A doctor prescribes antibiotics for the treatment of a bacterial infection. It is not effective against viruses.
Know whether an infection is bacterial or viral helps to effectively treat it.
Viruses cause most upper respiratory tract infections (URTIs), such as the common cold and flu. Antibiotics do not work against these viruses.
If people overuse antibiotics or use them incorrectly, the bacteria might become resistant. This means that the antibiotic becomes less effective against that type of bacterium, as the bacterium has been able to improve its defenses.
A doctor can prescribe a broad-spectrum antibiotic to treat a wide range of infections. A narrow-spectrum antibiotic is only effective against a few types of bacteria.
Some antibiotics attack aerobic bacteria, while others work against anaerobic bacteria. Aerobic bacteria need oxygen and anaerobic bacteria do not.
In some cases, a healthcare professional may provide antibiotics to prevent rather than treat an infection, as might be the case before surgery. This is the ‘prophylactic’ use of antibiotics. People commonly use these antibiotics before bowel and orthopedic surgery.
Antibiotics commonly cause the following side effects:
- upset stomach
- with certain antibiotics or prolonged use, fungal infections of the mouth, digestive tract, and vagina
Less common side effects of antibiotics include:
- formation of kidney stones, when taking sulphonamides
- abnormal blood clotting, when taking some cephalosporins)
- sensitivity to sunlight, when taking tetracyclines
- blood disorders, when taking trimethoprim
- deafness, when taking erythromycin and the aminoglycosides
Some people, especially older adults, may experience bowel inflammation, which can lead to severe, bloody diarrhea.
In less common instances, penicillins, cephalosporins, and erythromycin can also cause inflamed bowels.