Antibiotics are drugs used to treat bacterial infections. Antibiotics work by stopping bacteria from reproducing (bacteriostatic) or by destroying bacteria (bactericidal). Antibiotics don’t work at all against infections caused by viruses (colds, flu) and fungi (yeast infections).

A bacterial infection occurs when bacteria grow out of control in your body. Bacteria can destroy tissues and organs, or they can interfere with bodily processes or functions, so this can be a pretty serious problem. Some infections, if serious enough, can lead to death.

There are many classes of antibiotics, which work in different ways to either stop the bacteria from growing, or to kill it. Antibiotics that attack a wide range of bacteria are called “broad-spectrum antibiotics”. Those that attack one type of bacteria are called “narrow-spectrum antibiotics”.

How do antibiotics treat an infection?
When you take antibiotics, they are absorbed into your bloodstream through your digestive system, and are transported throughout the body. When they reach the area of infection, they attack the bacteria. The number of bacteria then begins to decrease.

You may feel cured after a few days, and you may want to stop taking the antibiotic. If you do this, the bacteria that remain in the area will begin to reproduce again, and you will just end up with another infection. It is extremely important to take antibiotics for the full time prescribed in order to get rid of all of the harmful bacteria.

What about resistance to antibiotics?
While you take antibiotics, the number of bacteria decreases until there are almost none left. The ones that are killed off first are the weakest ones, and the few left may have been unaffected, or resistant to the antibiotic. Fortunately, our immune system can recognise these leftover bacteria and eliminate them.

However, if you stop taking the antibiotics before the prescribed time, the resistant bacteria will be numerous enough to create another infection, and a new antibiotic will have to be used. This can lead to bacteria that are resistant to all known antibiotics.

What are the possible side effects of antibiotics?
Naturally occurring bacteria in the body, like the intestinal bacteria needed for digestion, can also be affected by antibiotics. This can cause side effects like diarrhea or vaginal yeast infections in women. Intestinal bacteria will return to proper levels after the antibiotics are finished, because they are replenished by the foods we eat. Eating yoghurt containing live bacterial culture may help with diarrhea.

Vaginal yeast infections occur when the natural balance of bacteria and yeast in the vagina is thrown off, and the yeast has an opportunity to overgrow. Inserting plain yoghurt, containing the lactobacillus bacteria, into the vagina can help. Test the yoghurt on the external part of your vagina first, to make sure your skin doesn’t react badly.

Other side effects can occur, so check with a health care professional.

More about antibiotics
WARNING! Antibiotics may decrease the effectiveness of birth control pills. An alternate form of birth control should be used.

Always take the full dose of antibiotics. Do not stop when you start feeling better. Be sure to follow the instructions, e.g. taking the pills with meals.

Do not pressure your doctor for a prescription for antibiotics for viral infections, such as the cold or the flu. This is one of the main factors leading to an increase in bacterial resistance to antibiotics.

Antibiotics can be used to prevent infection during dental work.

Tell your doctor about any allergies to antibiotics you may have.

Alcohol should be avoided when taking antibiotics as it competes with liver enzymes, which break down the antibiotics. Especially avoid taking the antibiotic Flagyl with alcohol, because you may experience a severe vomiting reaction.