Antibiotics are a large group of drugs, each of which is characterized by its spectrum of action, indications for use. All antibiotics prescribed for a bacterial infection can act bactericidal or bacteriostatically on microorganisms. In the first case, bacteria die, and in the second, microorganisms are deprived of the opportunity to multiply. The absence of offspring leads to the death of pathogens and their complete disappearance.
Antibiotics used for bacterial infections can be administered into the body in a variety of ways. Preparations are produced for all possible routes of administration. There are tablets and capsules for oral administration, solutions for intravenous, intramuscular injection, sprays, ointments, suppositories.
Reception Features
Applicationantibiotics for a bacterial infection should be performed according to the following rules:
- Antibiotics should be prescribed by a doctor. The choice of drug depends on the nature and severity of the pathology.
- Antimicrobials are not used to treat viral infections.
- The effectiveness of antibiotic therapy is assessed in the first three days of treatment. If it has the desired effect, then the course continues. Otherwise, the doctor decides whether to replace the medication.
- During taking the drug, side effects may occur in the form of nausea, the appearance of an unpleasant aftertaste in the mouth. These manifestations do not always require discontinuation of the drug. Often it is enough to adjust the dose to reduce the side effects of the drug. The exact measures to neutralize the side effects of the drug are determined by the attending physician.
- Diarrhea may occur as a result of ingestion. If loose stools appear, you should immediately consult a doctor. Do not try to self-treat diarrhea that occurs while taking an antimicrobial.
- Do not change the dosage yourself. In small doses, drugs can be dangerous as microorganisms develop resistance to them.
- The drug should be used strictly at a certain time to maintain the desired level of concentration of the substance in the blood.
- Antibiotics should be used strictly either before meals or after - depending on the type of drug. Otherwise, the medicine will be worse absorbed. Features of the reception must be clarified with the attending physician.
Classificationantibiotics
Over the past hundred years, a huge number of antibiotics have been created. With a bacterial infection, a variety of drugs are used. Some of the antibiotics are only being introduced into clinical practice, and some are no longer used.
All antimicrobials are divided into the following types:
- By origin. Allocate natural, semi-synthetic, synthetic drugs. Natural ones are obtained from plant and animal cells. Semi-synthetic - by modifying natural molecules, while synthetic ones are obtained in the laboratory.
- Dividing in the direction of action. Antibiotics can be used for intestinal, neurosurgical infections, pathologies of the respiratory, urinary tract, reproductive system, skin, soft tissues, etc.
Resistance
Resistance can occur in children and adults when taking antibiotics for a bacterial infection. The main mechanism for the development of this phenomenon is a genetic mutation that occurs in bacteria. Bacteria receive information about genetic resistance and carry this information to the next generations. As a result, the metabolism of microorganisms changes, immunity to a certain substance appears. Antibiotic target disappears.
Resistance occurs due to the irregular use of drugs, contrary to the instructions. The reason may also be self-treatment, without consulting a doctor.
The action of antibiotics
Whenbacterial or viral infection, antibiotics are prescribed, thus understandable. They have no effect on viruses, but can be prescribed when attached to a viral bacterial infection.
Antibiotics are divided into two large groups:
- Bacteriostatic. They prevent the reproduction of pathogenic microorganisms.
- Bactericidal. Drugs that cause the death of pathogenic microorganisms.
The mechanism of biological action of both groups is based on the following:
- cell wall synthesis is suppressed - penicillins, cephalosporins, fosfomycins, glycopeptides, carbapenems, monobactams act on bacteria in a similar way;
- affects overwhelmingly the functions of DNA: this includes preparations of the trimethoprim groups, nitroimidazoles, ansamycins, nitrofurans;
- suppression of protein synthesis on ribosomes: macrolides, lincosamines, levomycetins, aminoglycosides, tetracyclines;
- membrane dysfunction: imidazoles, polymyxins, gramicidins, polyene drugs.
Groups of antibacterial drugs
Bacterial infections are treated with antibiotics, which must be selected individually for each patient.
The classification of antibiotics is based on the chemical structure. So, one group includes drugs that have a similar formula, but differ in some fragments.
Penicillin group
This is one of the first groups of drugs derived from penicillin. This group includes:natural benzylpenicillin produced by fungi; semi-synthetic drugs "Methicillin", "Nafcillin"; synthetic medicines such as Carbenicillin, Ticarcillin.
This group includes other penicillin medicines: Amoxicillin, Oxacillin, Ampicillin, Amoxiclav. All of them have a wide spectrum of activity, are safe for use by children and pregnant women, but often cause allergic reactions.
Cephalosporin group
Cephalosporin antibiotics for bacterial infections in children and adults are used in cases where the penicillin series does not give the desired result or patients have an allergic reaction.
Cephalosporins are produced by fungi and are capable of killing microorganisms. There are several generations of antibacterial drugs:
- first generation: Cefalexin, Cephradin, Cefazolin;
- second generation: Cefsulodin, Cefamandol, Cefuroxime;
- third generation: Cefotaxime, Cefodizim, Ceftazidime;
- fourth generation: "Cefpirom".
The difference between generations is in the spectrum of action. More recent drugs have a broad spectrum of action and are considered more effective.
Macrolides
For a bacterial infection, macrolide antibiotics are prescribed. They are considered the safest means that even pregnant women can use. Representatives of the group are: "Azithromycin", "Josamycin",Leukomycin, Rovamycin.
The advantage of the drugs of the group is the ability to penetrate into the cells of the human body. Because of this specificity, macrolides are used to treat mycoplasmosis, chlamydia.
Aminoglycosides
Bacterial infection is treated with antibiotics with a spectrum of action that allows you to destroy pathogenic microorganisms. Thus, drugs of the aminoglycoside group are effective against gram-negative aerobic bacteria. These drugs are toxic and can lead to serious complications. They are prescribed in rare cases for the treatment of furunculosis, an infection of the genitourinary system. The drugs of the group include Gentamicin, Amikacin, Kanamycin.
Tetracycline group
Antibiotic treatment of bacterial infection in children and adults involves the use of the tetracycline group. It includes synthetic and semi-synthetic drugs, such as Tetracycline, Minocycline, Doxycycline. They are effective against most pathogens.
The disadvantage of drugs is that they can cause resistance in bacteria. Moreover, if this occurs, then the microorganisms will be resistant to all drugs of the group.
Fluoroquinolones
This group includes fully synthetic drugs that do not have a natural analogue. All fluoroquinolones are divided into two groups. The first includes drugs such as Pefloxacin, Ciprofloxacin, Norfloxacin. The second group includes Levofloxacin, Moxifloxacin.
Fluoroquinolones are most commonly used to treatrespiratory tract, ENT organs.
Other bands
And what antibiotics can still be prescribed for a bacterial infection? In addition to the above, there are the following groups:
- Lincosamides. It includes the natural antibiotic Lincomycin and its derivative Clindamycin. The effect achieved depends on the concentration of the drug.
- Carbapenems. Modern drugs that have an effect on various microorganisms. Preparations of this group belong to reserve antibiotics and are used in difficult cases when other medicines are ineffective. The representatives of the group are "Imipenem", "Ertapenem".
- In a separate group allocate antibiotics that affect the tubercle bacillus. These include: "Rifampicin", "Isoniazid" and others.
- For the treatment of fungal infections, antifungal antibacterial agents are used: Nystatin, Fluconazole.
Application
When choosing a therapy, the doctor must determine which antibiotics treat the bacterial infection most effectively. After that, the form of the drug, the scheme of application is determined. The main routes of drug administration include:
- Oral method. Suggests taking antibiotics by mouth. Take the drug in the form of tablets, capsules, syrup, powder. The frequency of administration depends on the drug. For example, penicillins are used four times a day, one tablet, and "Azithromycin" - one tablet a day. Each drug has its own characteristics of taking: during or after a meal, before meals. It depends on correct use.the effectiveness of the drug, the severity of side effects. Children are most often prescribed antibiotics in the form of syrup. This is because it is easier for them to take liquid dosage form than tablets or capsules.
- Injections. The drug is most active when administered intramuscularly or intravenously. The disadvantage of the method is the soreness of the injection. This method of administration is used for severe and moderate disease.
- Local use. Antibiotics are available in the form of ointments, gels, creams intended for topical use. This method is used to deliver the active substance directly to the site of inflammation on the skin or mucous membranes. Local remedies are used in ophthalmology, dermatology.
What antibiotics to take for a bacterial infection for a particular patient, only the doctor decides. He also determines the method of application, taking into account the level of absorption, the general condition of the patient. Some medications are given only one way.
Drug sensitivity
Every organism gets used to any conditions, and microorganisms are no exception. With prolonged exposure to antimicrobials, bacteria develop resistance. Because of this feature, the concept of sustainability was introduced.
The choice of the drug is based on the knowledge of scientists about the sensitivity of bacteria to the antibiotic. Under ideal conditions, doctors select drugs that affect the bacteria that led to the pathology. However, in order to carry outanalysis to identify the sensitivity of the pathogen to the drug, it takes several days, and during this time the infection can lead to a serious complication, up to death. In order not to waste time, doctors select the drug taking into account the epidemiological situation in the region. Broad-spectrum drugs are usually used.
As soon as the result of the analysis is ready and the pathogen becomes known, the doctor can change the drug to a more effective one. Also, the replacement of the drug is performed if there is no effect on the third day of therapy.
Effectiveness of drugs
Is it necessary to take antibiotics for a bacterial infection and do they always help? With a bacterial and fungal infection, it is necessary to take an antimicrobial drug. This is the only way to get rid of pathogens.
There are bacteria that exist peacefully in the human body. They are considered opportunistic pathogens. But under certain conditions, these "harmless" bacteria become the cause of the disease. An example is the penetration of E. coli into the prostate through the urinary tract.
Alcohol and antibiotics
When taking alcohol and antibiotics at the same time, the load on the liver increases. The presence of an antibacterial drug and an alcohol-containing drink in the blood leads to a strong load on the liver - it does not have time to neutralize alcohol. As a result, the likelihood of developing unpleasant symptoms such as nausea, indigestion, and vomiting is increased.
Some drugs interact chemically with alcohol. These include Metronidazole, Levomycetin and others. Concomitant use of alcohol and similar antibiotics can lead to convulsions, shortness of breath and even death.
