How many antibiotic are there

Each antibiotic is effective only against certain bacteria. In selecting an antibiotic to treat a person with an infection, doctors estimate which bacteria are likely to be the cause. For example, some infections are caused only by certain types of bacteria. Sometimes one antibiotic is predictably effective against all of the bacteria that are most likely to be causing an infection and so further testing may not be needed.

If infections may be caused by many different types of bacteria or by bacteria that are not predictably susceptible to antibiotics, a laboratory is asked to identify the infecting bacteria Diagnosis of Infectious Disease Infectious diseases are caused by microorganisms, such as bacteria, viruses, fungi, and parasites.

The infecting bacteria are then tested for susceptibility to a variety of antibiotics. Results of these tests usually take a day or two and thus cannot guide the initial choice of antibiotic. In such cases, doctors typically start treatment with an antibiotic that is effective against the bacteria most likely to be causing the infection.

When test results are back, doctors change the antibiotic if needed. Antibiotics that are effective in the laboratory do not necessarily work in an infected person.

The effectiveness of the treatment depends on. How well the drug is absorbed into the bloodstream for drugs taken by mouth Oral route Drugs are introduced into the body by several routes. They may be Taken by mouth orally Given by injection into a vein intravenously, IV , into a muscle intramuscularly, IM , into the space How much of the drug reaches the sites of infection in the body see Drug Distribution Drug Distribution Drug distribution refers to the movement of a drug to and from the blood and various tissues of the body for example, fat, muscle, and brain tissue and the relative proportions of drug in How quickly the body eliminates the drug see Drug Elimination Drug Elimination Drug elimination is the removal of drugs from the body.

See also Introduction to Administration and Kinetics of Drugs. All drugs are eventually eliminated from the body. They may be eliminated Doctors also consider how hard it may be for people to take antibiotics for the entire time prescribed and complete the full course of treatment.

People may find it more difficult to complete treatment if the drug must be taken very often or only at specific times such as before meals, during meals, or after meals. Severe infections, particularly during the first days when the bacteria's susceptibility to antibiotics is not known. Infections caused by more than one type of bacteria if each type is susceptible to a different antibiotic. Bacteria, like all living organisms, change over time in response to environmental challenges.

Because of the widespread use and misuse of antibiotics, bacteria are constantly exposed to these drugs. Although many bacteria die when exposed to antibiotics, some develop resistance Antibiotic resistance Bacteria are microscopic, single-celled organisms.

For example, 50 years ago, Staphylococcus aureus a common cause of skin infections was very sensitive to penicillin. But over time, strains of this bacteria developed an enzyme able to break down penicillin, making the drug ineffective.

Researchers responded by developing a form of penicillin that the enzyme could not break down, but after a few years, the bacteria adapted and became resistant to this modified penicillin.

Other bacteria have also developed resistance to antibiotics. Medical research continues to develop drugs to combat bacteria. But people can help prevent the development of resistance in bacteria by.

Taking antibiotics only when necessary that is, people should take antibiotics only for infections caused by bacteria, not for those caused by viruses such as a cold or the flu.

Not asking doctors to prescribe antibiotics for viral infections, such as the common cold or the flu. If a virus is causing the infection, taking antibiotics is useless and can contribute to the development of resistance in bacteria. For severe bacterial infections, antibiotics are usually first given by injection Oral route Drugs are introduced into the body by several routes.

When the infection is controlled, antibiotics can then be taken by mouth Oral route Drugs are introduced into the body by several routes. When doctors prescribe antibiotics for older people, they may prescribe a lower dose than usual because the kidneys tend to function less well as people age. In such cases, the kidneys may not be able to eliminate antibiotics from the body as effectively, increasing the risk of side effects. See also Aging and Drugs Aging and Drugs Drugs, the most common medical intervention, are an important part of medical care for older people.

Without drugs, many older people would function less well or die at an earlier age. What other drugs the person is taking because older people tend to take many drugs and drug interactions are a risk. Whether the person has family members or caregivers who can help the person take the antibiotic as prescribed. Whether the person lives in a nursing home because different bacteria may cause infections in such situations. Antibiotics need to be taken until the infecting bacteria are eliminated from the body, which may be days after the symptoms disappear.

Antibiotics are rarely given for fewer than 5 days. An exception is certain uncomplicated urinary tract infections Overview of Urinary Tract Infections UTIs In healthy people, urine in the bladder is sterile—no bacteria or other infectious organisms are present. The tube that carries urine from the bladder out of the body urethra contains no bacteria Stopping treatment too soon can result in a return of the infection. A doctor, nurse, or pharmacist can explain how the prescribed antibiotic should be taken and what side effects it may have.

Some antibiotics must be taken on an empty stomach. Others should be taken with food. Metronidazole Metronidazole and Tinidazole Metronidazole is an antibiotic used to treat pelvic, abdominal, soft-tissue, gum, and tooth infections and abscesses in the lungs or brain. Also, some antibiotics can interact with other drugs that people may be taking, possibly reducing the effectiveness or increasing the side effects of the antibiotic or the other drugs. Some antibiotics make the skin sensitive to sunlight Chemical photosensitivity Photosensitivity, sometimes referred to as a sun allergy, is an immune system reaction that is triggered by sunlight.

Sunlight can trigger immune system reactions. People develop itchy eruptions Antibiotics are sometimes used to prevent infections called prophylaxis. For example, prophylactic antibiotics may be given to. Some people with abnormal or artificial heart valves before dental and surgical procedures to prevent bacteria from infecting the damaged or artificial valves such procedures can allow bacteria to enter the body.

People undergoing surgery that has a high risk of introducing an infection such as major orthopedic or intestinal surgery. To avoid the development of antibiotic resistance Antibiotic resistance Bacteria are microscopic, single-celled organisms. Such a breakdown can lead to infections, which can even be caused by microorganisms that normally They may need to take the antibiotics for a long time.

Generally, antibiotics are used during pregnancy only when the benefits of treatment outweigh the risks. Here are some questions you may want to ask before taking antibiotics:. Antibiotics are practically a miracle drug.

When they were first invented, they saved countless lives and, to this day, continue to do so. If you or your child develops a bacterial infection, one of the keys to returning to health could be an antibiotic.

Diabetes is a chronic condition that requires careful management to prevent complications including kidney Pregnancy affects every woman differently, which means not all women will experience the same early symptoms Prenatal vitamins can provide you with the nutrients you need to give birth to a healthy baby. If you are A hair follicle drug test can detect whether a person has illicit or prescription drugs in their system.

If you are living with diabetes, managing your A1c levels is critical to staying healthy and reducing your The A1c blood test can provide you with your average blood sugar level over the last three months.

This test A mouth swab drug test can detect whether you have illicit or prescription drugs in your system. Blood tests are usually performed at every routine medical checkup, but many times, the results can be Solv Health. Adult Child. Quality healthcare is just a click away with the Solv App Book same-day care for you and your family. Find top providers near you.

Choose in-person or video visits. Manage visits on-the-go. Updated on Nov 20, For example, if you have pneumonia , the doctor knows what kinds of bacteria typically cause most cases of pneumonia.

He or she will choose the antibiotic that best combats those kinds of bacteria. Even if you are pregnant or breastfeeding there are a number of antibiotics that are thought to be safe to take.

It is important to take antibiotics in the correct way. If you do not, this may reduce how well they work. For example, some antibiotics need to be taken with food and others should be taken on an empty stomach. If you do not take your antibiotics in the right way it will affect how much of them get into your body their absorption and therefore they may not work as well. So, follow the instructions as given by your doctor and on the leaflet that comes with the antibiotic you are prescribed.

Always take the entire course of antibiotics as directed by your doctor. Even though you may feel better before your medicine is entirely gone, follow through and take the entire course.

This is important for your healing. If an antibiotic is stopped in mid-course, germs bacteria may be partially treated and not completely killed. Bacteria may then become resistant to that antibiotic. Overuse of antibiotics has led to some bacteria changing their form or structure mutating and becoming resistant to some antibiotics, which may then not work when really needed. For example, meticillin-resistant Staphylococcus aureus MRSA is a bacterium that has become resistant to many different antibiotics and is difficult to treat.

Other bacteria produce chemicals called enzymes such as extended-spectrum beta-lactamases ESBLs which allow them to be resistant to certain antibiotics. Resistance to antibiotics has become a major health threat globally, as antibiotics are life-saving for serious illnesses. So if your health professional says antibiotics are not needed for your condition, do not ask for them. Your health professional will explain in what circumstances you might need antibiotics and what symptoms should prompt you to return for another check.

If your illness has changed, or you have developed a secondary infection, antibiotics may be needed after all. Health professionals follow guidelines to help reduce unnecessary use of antibiotics. It is not possible in this leaflet to list all the possible side-effects of each antibiotic. However, as with all medicines, there are a number of side-effects that have been reported with each of the different antibiotics.

If you want more information specific to your antibiotic then you should read the information leaflet that comes with the medicine.

Most side-effects of antibiotics are not serious. Common side-effects include soft stools faeces , diarrhoea, or mild stomach upset such as feeling sick nausea. Less commonly, some people have an allergic reaction to an antibiotic and some have died from a severe allergic reaction - this is very rare. Antibiotics can kill off normal defence bacteria which live in the bowel and vagina.

This may then allow thrush or other bad bacteria to grow. Some antibiotics may interact with other medicines that you might take. This may cause reactions, or reduce the effectiveness of one or other of the treatments. So, when you are prescribed an antibiotic you should tell a doctor if you take other medicines. In the past it was recommended that, if you were taking antibiotics and were also taking the pill , you should use additional contraception.

This is no longer the current recommendation after more recent evidence has been reviewed. Antibiotics other than one called rifampicin do not interfere with the effectiveness of the pill. You should continue taking your pill as normal if you also need to take any antibiotics. No, in the UK they are only available from your chemist, with a doctor's prescription. In some other parts of the world they are available over the counter. However, to reduce the problem of resistance due to inappropriate use of antibiotics, it is best to always obtain medical advice before buying antibiotics.

The length of treatment varies a lot. It depends on what kind of infection you have, how severe it is and how quickly you get better after starting treatment. Treatment can be:. It is very rare for anyone not to be able to take some type of antibiotic.

The main reason why you may not be able to take an antibiotic is if you have had an allergic reaction to an antibiotic in the past. Even if you have had an allergic reaction to one antibiotic, your doctor or health professional will be able to choose a different type of antibiotic, which you will be able to take. If you are pregnant, there are certain antibiotics you should not take, but your health professional will be able to advise on which one is suitable if an antibiotic is needed.