Antibiotics may be informally defined as the subgroup of anti-infectives that are derived from bacterial sources and are used to treat bacterial infections. Other classes of drugs, most notably the sulfonamides, may be effective antibacterials.
What are antibiotics?
The US National Library of Medicine1 says that antibiotics – powerful medicines that fight bacterial infections – can save lives when used properly. Antibiotics either stop bacteria from reproducing or kill them. “Your body’s natural defenses can usually take it from there.” Before bacteria can multiply and cause symptoms, the body’s immune system can usually destroy them. We have special white blood cells that attack harmful bacteria. Even if symptoms do occur, our immune system can usually cope and fight off the infection.
What are antibiotics used for?
An antibiotic is given for the treatment of an infection caused by bacteria. Antibiotics target microorganisms such as bacteria, fungi and parasites. However, they are not effective against viruses. If you have an infection it is important to know whether it is caused by bacteria or a virus. Most upper respiratory tract infections, such as the common cold and sore throats are generally caused by viruses – antibiotics do not work against these viruses. If antibiotics are overused or used incorrectly there is a risk that the bacteria will become resistant – the antibiotic becomes less effective against that type of bacterium.
When To Use Antibiotics
Antibiotics are specific for the type of bacteria being treated and, in general, cannot be interchanged from one infection to another. When antibiotics are used correctly, they are usually safe with few side effects.
However, as with most drugs, antibiotics can lead to side effects that may range from being a nuisance to serious or life-threatening. In infants and the elderly, in patients with kidney or liver disease, in pregnant or breastfeeding women, and in many other patient groups antibiotic doses may need to be adjusted based upon the specific characteristics of the patient, like kidney or liver function, weight, or age. Drug interactions can also be common with antibiotics. Health care providers are able to assess each patient individually to determine the correct antibiotic and dose.
What are the side-effects of antibiotics?
An antibiotic side effect is an unwanted reaction that occurs in addition to the desirable therapeutic action of the antibiotic. When used appropriately, antibiotics are relatively safe with very few side effects. However, like any drug, antibiotic side effects can occur and may interfere with the patient’s ability to tolerate and finish the course of medication. Common side effects with antibiotics include rash, diarrhea, upset stomach, and fungal (yeast) infections.
Antibiotic reactions can range from mild allergic reactions to severe and debilitating adverse events. Antibiotic side effects are extremely variable from patient to patient and from antibiotic to antibiotic. However, there are some common side effects that may occur within antibiotic drug classes, as described in Table 1. If a patient is experiencing a bothersome or serious antibiotic side effect, they should contact their health care provider. The outcomes may include staying on the same antibiotic and managing the side effect, adjusting the dose, or switching to a different antibiotic.
Usually, antibiotic treatment should not be stopped without a health care provider’s approval. Stopping the antibiotic may allow the infection to worsen and may lead to antibiotic resistance. Even if the infection appears to have cleared up before all of the medication is gone, the full course of antibiotic treatment should always be completed unless told otherwise by a health care provider.