Which drug has a bactericidal effect? Bactericidal action - what is it? Antibacterial drugs

Treatment of bacterial infections today is impossible without the use of antibiotics. Microorganisms tend to become resistant to chemical compounds over time, and old drugs are often ineffective. Therefore, pharmaceutical laboratories are constantly looking for new formulas. In many cases, infectious disease specialists prefer to use new generation broad-spectrum antibiotics, the list of which includes drugs with different active ingredients.

Antibiotics act only on bacterial cells and are not able to kill viral particles.

Based on their spectrum of action, these drugs are divided into two large groups:

• narrowly targeted, coping with a limited number of pathogens;
• broad spectrum of action, fighting different groups of pathogens.

In the case where the pathogen is known exactly, antibiotics of the first group can be used. If the infection is complex and combined, or the pathogen has not been identified in the laboratory, drugs of the second group are used.

Based on the principle of action, antibiotics can also be divided into two groups:

• bactericides – drugs that kill bacterial cells;
• bacteriostatics are drugs that stop the proliferation of microorganisms, but are not able to kill them.

Bacteriostatics are safer for the body, therefore, for mild forms of infections, preference is given to this group of antibiotics. They allow you to temporarily restrain the growth of bacteria and wait for them to die on their own. Severe infections are treated with bactericidal drugs.

List of new generation broad-spectrum antibiotics

The division of antibiotics into generations is heterogeneous. For example, cephalosporin drugs and fluoroquinolones are divided into 4 generations, macrolides and aminoglycosides - into 3:

Group of drugs	Generations of drugs	Drug names
Cephalosporins	I	"Cefazolin" "Cephalexin"
	II	"Cefuroxime" "Cefaclor"
	III	"Cefotaxime" "Cefixime"
	IV	"Cefepime" "Cefpirom"
Macrolides	I	"Erythromycin"
	II	"Flurithromycin" "Clarithromycin" "Roxithromycin" "Midecamycin"
	III	"Azithromycin"
Fluoroquinolones	I	Oxolinic acid
	II	"Ofloxacin"
	III	"Levofloxacin"
	IV	"Moxifloxacin" "Gemifloxacin" "Gatifloxacin"
Aminoglycosides	I	"Streptomycin"
	II	"Gentamicin"
	III	"Amikacin" "Netilmicin" "Framycetin"

Unlike older drugs, new generation antibiotics affect beneficial flora much less, are absorbed faster, and have a less toxic effect on the liver. They are able to quickly accumulate the active substance in the tissues, due to which the frequency of doses is reduced and the intervals between them increase.

What medications should I take depending on the disease?

Often the same broad-spectrum drug is prescribed for different diseases. But this does not mean that you can do without preliminary diagnosis. Only a correct diagnosis allows you to adequately select an antibiotic.

Treatment of bronchitis

Bronchitis is a common infectious and inflammatory disease that can lead to serious complications. The following medications may be prescribed to treat bronchitis:

Drug name		Contraindications	Dosage
"Sumamed"		age up to 6 months;	Children over 3 years old – 2 tablets of 125 mg per day. Children under 3 years old – 2.5 to 5 ml of suspension per day.
"Avelox"	A group of fluoroquinolones, the active substance is Moxifloxacin.	pregnancy and lactation; age under 18 years; heart rhythm disturbances; severe liver diseases.	1 tablet 400 mg per day
"Gatispan"	A group of fluoroquinolones, the active substance is Gatifloxacin.	pregnancy and lactation; age under 18 years; diabetes mellitus; heart rhythm disturbances; convulsions.	1 tablet 400 mg per day
"Flemoxin Solutab"		lymphocytic leukemia; gastrointestinal pathologies; pregnancy and lactation; infectious mononucleosis.

Along with antibiotics, mucolytic and anti-inflammatory drugs are used in the treatment of bronchitis.

For pneumonia

Pneumonia should never be treated independently at home. This disease requires mandatory hospitalization and serious therapy with intramuscular or intravenous antibiotics.

The following injection drugs can be used to treat pneumonia in a hospital:

• "Ticarcillin";
• "Carbenicillin";
• "Cefepime";
• "Meropenem".

In some cases, antibiotics are also prescribed in tablets. These may be drugs:

• "Tigeron";
• "Gatispan";
• "Sumamed";
• "Avelox".

The dosage and frequency of doses in this case is determined individually, based on the patient’s condition and therapeutic strategy.

Antibiotics for sinusitis

The decision to prescribe antibiotics for the treatment of sinusitis is made by an ENT doctor. Therapy with these drugs is mandatory if there is purulent discharge from the sinuses and intense headaches:

Drug name	Group and active substance	Contraindications	Dosage
"AzitRus"	A group of macrolides, the active ingredient is Azithromycin.	severe liver dysfunction; age up to 3 years; individual intolerance.	Adults and children over 12 years old – 1 capsule or tablet of 500 mg per day. Children over 3 years old – 10 mg per 1 kg of weight per day.
"Faktiv"	A group of fluoroquinolones, the active substance is Gemifloxacin.	pregnancy and lactation; age under 18 years; heart rhythm disturbances; severe liver diseases.	1 tablet 320 mg per day
"Flemoclav Solutab"	Penicillin group, active ingredient – ​​Amoxicillin.	lymphocytic leukemia; gastrointestinal pathologies; pregnancy and lactation; age up to 3 years; infectious mononucleosis.	Adults and children over 12 years old – 1 tablet of 500 mg 3 times a day. Children under 12 years old – 25 mg per 1 kg of body weight per day.

Before prescribing antibiotics, an ENT doctor usually gives a referral for a bacterial culture and an antibiogram to determine the type of pathogen and its sensitivity to a particular active substance.

For sore throat

In everyday life, sore throat is commonly called acute tonsillitis - inflammation of the tonsils caused by viruses or bacteria. The bacterial form of sore throat is caused by streptococci or staphylococci, and this disease can only be treated with antibiotics:

Drug name	Group and active substance	Contraindications	Dosage
"Macropen"	A group of macrolides, the active substance is Midecamycin.	liver diseases; age up to 3 years; individual intolerance.	Adults and children weighing over 30 kg – 1 tablet of 400 mg 3 times a day.
"Rulid"	A group of macrolides, the active ingredient is Roxithromycin.	age up to 2 months; pregnancy and lactation.	Adults and children weighing over 40 kg – 2 tablets of 150 mg 1-2 times a day. In other cases, the dosage is calculated individually.
"Flemoxin Solutab"	Penicillin group, active ingredient – ​​Amoxicillin.	lymphocytic leukemia; gastrointestinal pathologies; pregnancy and lactation; infectious mononucleosis.	Adults – 1 tablet 500 mg 2 times a day. Children over 10 years old – 2 tablets of 250 mg 2 times a day. Children over 3 years old – 1 tablet 250 mg 3 times a day. Children under 3 years old – 1 tablet 125 mg 3 times a day.

It is important to understand that if acute tonsillitis is not bacterial, but viral in nature, it is useless to treat it with antibiotics. Only a doctor can distinguish between these two forms of the disease, so you should not take any medications without his consultation.

Colds and flu

Respiratory infections, which in everyday life are called colds, as well as influenza are caused by viruses. Therefore, antibiotics are used in their treatment only in one case: if the disease becomes complicated and a bacterial infection joins the viral infection.

In such situations, therapy is usually started with penicillin antibiotics:

• "Flemoxin Solutab";
• "Flemoclav Solutab".

If no improvement is observed after 72 hours after starting to take these drugs, new generation macrolides are added to therapy:

• "Sumamed";
• "Rulid";
• "AzitRus".

The regimen for taking antibiotics for the treatment of respiratory infections is standard, but medical supervision is also necessary in this case.

Infections of the genitourinary system

Urogenital infections can be caused by pathogens of different nature - viruses, fungi, bacteria, protozoa. Therefore, it makes sense to start treatment only after a thorough laboratory diagnosis and determination of the type of pathogen.

In mild cases, the infection can be removed from the urinary tract using the following medications:

• “Furadonin” – 2 mg per 1 kg of weight 3 times a day;
• “Furazolidone” – 2 tablets 0.05 g 4 times a day;
• “Palin” – 1 capsule 2 times a day.

In more complex situations, when pathogens are highly resistant (resistant) to chemical influences, broad-spectrum antibiotics can be prescribed:

Drug name	Group and active substance	Contraindications	Dosage
"Abaktal"	A group of fluoroquinolones, the active substance is Pefloxacin.	pregnancy and lactation; age under 18 years; hemolytic anemia; individual intolerance.	1 tablet 400 mg 1-2 times a day.
"Monural"	A derivative of phosphonic acid, the active substance is Fosfomycin.	age up to 5 years; individual intolerance; severe renal failure.	Single dose – dissolve 3 g of powder in 50 g of water and take on an empty stomach before bed.
"Cefixime"	A group of cephalosporins, the active substance is Cefixime.	individual intolerance.	Adults and children over 12 years old – 1 tablet of 400 mg 1 time per day. Children under 12 years old – 8 mg per 1 kg of weight 1 time per day.

Along with antibiotics, in the treatment of genitourinary infections, plenty of fluids and diuretics are prescribed. In severe cases, injections of the drug Amikacin are advisable.

Antifungal drugs

To treat fungal infections, drugs with fungistatic or fungicidal effects are used. They differ from the drugs listed above and are classified into a separate class, within which there are three groups:

As in the treatment of bacterial infections, therapy for fungal diseases requires accurate diagnosis of the pathogen and strict supervision by a specialist.

For eye disease

Antibiotics for the treatment of eye diseases are available in the form of ointments or drops. They are prescribed if the ophthalmologist has diagnosed conjunctivitis, blepharitis, meibomitis, keratitis and a number of other infections.

Most often, therapy is carried out using the following drugs:

• "Tsipromed" - drops containing Ciprofloxacin;
• “Albucid” – drops with sulfacetamide;
• "Dilaterol" - drops based on tobramycin;
• “Tobrex” is an analogue of “Dilaterol” in the form of an ointment;
• "Kolbiocin" is a multicomponent ointment containing tetracycline, chloramphenicol and sodium colistimethate.

A specific drug is prescribed based on the diagnosis, severity of the disease and the individual characteristics of the patient.

Inexpensive new generation antibiotics

The cost of new generation antibiotics is never low, so you can save money only by buying inexpensive analogues. They are produced on the basis of the same active ingredients, however, the degree of chemical purification of such drugs may be lower, and the auxiliary substances for their production are the cheapest.

You can replace some expensive antibiotics using the following table:

Another way to save money is to buy older antibiotics, not the latest generation.

For example, in many cases the following proven antibacterial drugs can help out:

• "Erythromycin";
• "Ceftriaxone";
• "Bicillin";
• "Cefazolin";
• "Ampicillin."

If more than 72 hours have passed after starting treatment with inexpensive antibiotics, and no improvement is observed, you should urgently consult a doctor and change the drug.

Can it be used during pregnancy?

Antibiotics during pregnancy are prescribed by doctors only in emergency cases and after a thorough analysis of possible risks.

But even in such situations, drugs of the following groups are not used:

• all fluoroquinolones;
• macrolides based on roxithromycin, clarithromycin, midecamycin;
• all aminoglycosides.

Only the attending physician can decide on the advisability of prescribing antibiotics during pregnancy. Self-administration of any medications, even relatively safe ones and those belonging to the new generation, is strictly prohibited.

Antibiotics are a group of drugs that can inhibit the growth and development of living cells. They are most often used to treat infectious processes caused by various strains of bacteria. The first drug was discovered in 1928 by British bacteriologist Alexander Fleming. However, some antibiotics are also prescribed for cancer pathologies, as a component of combination chemotherapy. This group of drugs has practically no effect on viruses, with the exception of some tetracyclines. In modern pharmacology, the term “antibiotics” is increasingly being replaced by “antibacterial drugs”.

They were the first to synthesize drugs from the penicillin group. They have helped to significantly reduce the mortality rate of diseases such as pneumonia, sepsis, meningitis, gangrene and syphilis. Over time, due to the active use of antibiotics, many microorganisms began to develop resistance to them. Therefore, the search for new groups of antibacterial drugs has become an important task.

Gradually, pharmaceutical companies synthesized and began to produce cephalosporins, macrolides, fluoroquinolones, tetracyclines, chloramphenicol, nitrofurans, aminoglycosides, carbapenems and other antibiotics.

Antibiotics and their classification

The main pharmacological classification of antibacterial drugs is based on their effect on microorganisms. Based on this characteristic, two groups of antibiotics are distinguished:

• bactericidal - drugs cause the death and lysis of microorganisms. This effect is due to the ability of antibiotics to inhibit membrane synthesis or suppress the production of DNA components. Penicillins, cephalosporins, fluoroquinolones, carbapenems, monobactams, glycopeptides and fosfomycin have this property.
• bacteriostatic - antibiotics can inhibit the synthesis of proteins by microbial cells, which makes their reproduction impossible. As a result, further development of the pathological process is limited. This action is typical for tetracyclines, macrolides, aminoglycosides, lincosamines and aminoglycosides.

Based on the spectrum of action, two groups of antibiotics are also distinguished:

• with broad - the drug can be used to treat pathologies caused by a large number of microorganisms;
• with a narrow one - the medicine affects individual strains and types of bacteria.

There is also a classification of antibacterial drugs according to their origin:

• natural - obtained from living organisms;
• semisynthetic antibiotics are modified molecules of natural analogues;
• synthetic - they are produced completely artificially in specialized laboratories.

Description of different groups of antibiotics

Beta-lactams

Penicillins

Historically, the first group of antibacterial drugs. Has a bactericidal effect on a wide range of microorganisms. Penicillins are divided into the following groups:

• natural penicillins (synthesized under normal conditions by fungi) - benzylpenicillin, phenoxymethylpenicillin;
• semisynthetic penicillins, which are more resistant to penicillinases, which significantly expands their spectrum of action - oxacillin, methicillin medications;
• with extended action - preparations of amoxicillin, ampicillin;
• penicillins with a broad effect on microorganisms - medications mezlocillin, azlocillin.

To reduce bacterial resistance and increase the chance of success of antibiotic therapy, penicillinase inhibitors - clavulanic acid, tazobactam and sulbactam - are actively added to penicillins. This is how the drugs Augmentin, Tazotsim, Tazrobida and others appeared.

These medications are used for infections of the respiratory (bronchitis, sinusitis, pneumonia, pharyngitis, laryngitis), genitourinary (cystitis, urethritis, prostatitis, gonorrhea), digestive (cholecystitis, dysentery) systems, syphilis and skin lesions. The most common side effects are allergic reactions (urticaria, anaphylactic shock, angioedema).

Penicillins are also the safest drugs for pregnant women and infants.

Cephalosporins

This group of antibiotics has a bactericidal effect on a large number of microorganisms. Today the following generations of cephalosporins are distinguished:

The vast majority of these medications exist only in injection form, so they are used mainly in clinics. Cephalosporins are the most popular antibacterial agents for use in hospitals.

These drugs are used to treat a huge number of diseases: pneumonia, meningitis, generalized infections, pyelonephritis, cystitis, inflammation of bones, soft tissues, lymphangitis and other pathologies. Hypersensitivity is common with the use of cephalosporins. Sometimes a transient decrease in creatinine clearance, muscle pain, cough, and increased bleeding (due to a decrease in vitamin K) are observed.

Carbapenems

They are a fairly new group of antibiotics. Like other beta-lactams, carbapenems have a bactericidal effect. A huge number of different strains of bacteria remain sensitive to this group of medications. Carbapenems are also resistant to enzymes synthesized by microorganisms. Data properties have led to them being considered rescue drugs when other antibacterial agents remain ineffective. However, their use is strictly limited due to concerns about the development of bacterial resistance. This group of drugs includes meropenem, doripenem, ertapenem, imipenem.

Carbapenems are used to treat sepsis, pneumonia, peritonitis, acute surgical pathologies of the abdominal cavity, meningitis, and endometritis. These drugs are also prescribed to patients with immunodeficiencies or due to neutropenia.

Side effects include dyspepsia, headache, thrombophlebitis, pseudomembranous colitis, convulsions and hypokalemia.

Monobactams

Monobactams act predominantly only on gram-negative flora. The clinic uses only one active substance from this group - aztreonam. Its advantages include resistance to most bacterial enzymes, which makes it the drug of choice when treatment with penicillins, cephalosporins and aminoglycosides is ineffective. Clinical guidelines recommend aztreonam for enterobacter infection. It is used only intravenously or intramuscularly.

Indications for use include sepsis, community-acquired pneumonia, peritonitis, infections of the pelvic organs, skin and musculoskeletal system. The use of aztreonam sometimes leads to the development of dyspeptic symptoms, jaundice, toxic hepatitis, headache, dizziness and allergic rash.

Macrolides

Medicines are also characterized by low toxicity, which allows them to be used during pregnancy and early childhood. They are divided into the following groups:

• natural ones, which were synthesized in the 50-60s of the last century - preparations of erythromycin, spiramycin, josamycin, midecamycin;
• prodrugs (converted to the active form after metabolism) - troleandomycin;
• semisynthetic - medications azithromycin, clarithromycin, dirithromycin, telithromycin.

Macrolides are used for many bacterial pathologies: peptic ulcer, bronchitis, pneumonia, infections of the ENT organs, dermatosis, Lyme disease, urethritis, cervicitis, erysipelas, impentigo. This group of medications should not be used for arrhythmias or renal failure.

Tetracyclines

Tetracyclines were first synthesized more than half a century ago. This group has a bacteriostatic effect against many strains of microbial flora. In high concentrations they also exhibit a bactericidal effect. A feature of tetracyclines is their ability to accumulate in bone tissue and tooth enamel.

On the one hand, this allows clinicians to actively use them in chronic osteomyelitis, and on the other hand, it disrupts the development of the skeleton in children. Therefore, they should absolutely not be used during pregnancy, lactation and under the age of 12 years. Tetracyclines, in addition to the drug of the same name, include doxycycline, oxytetracycline, minocycline and tigecycline.

They are used for various intestinal pathologies, brucellosis, leptospirosis, tularemia, actinomycosis, trachoma, Lyme disease, gonococcal infection and rickettsiosis. Contraindications also include porphyria, chronic liver diseases and individual intolerance.

Fluoroquinolones

Fluoroquinolones are a large group of antibacterial agents with a broad bactericidal effect on pathogenic microflora. All drugs are similar to nalidixic acid. The active use of fluoroquinolones began in the 70s of the last century. Today they are classified by generation:

• I - preparations of nalidixic and oxolinic acid;
• II - medications with ofloxacin, ciprofloxacin, norfloxacin, pefloxacin;
• III - levofloxacin preparations;
• IV - medications with gatifloxacin, moxifloxacin, gemifloxacin.

The latest generations of fluoroquinolones are called “respiratory”, due to their activity against microflora, which most often causes the development of pneumonia. They are also used to treat sinusitis, bronchitis, intestinal infections, prostatitis, gonorrhea, sepsis, tuberculosis and meningitis.

Among the disadvantages, it is necessary to highlight the fact that fluoroquinolones can influence the formation of the musculoskeletal system, therefore in childhood, pregnancy and lactation they can be prescribed only for health reasons. The first generation of drugs is also characterized by high hepato- and nephrotoxicity.

Aminoglycosides

Aminoglycosides have found active use in the treatment of bacterial infections caused by gram-negative flora. They have a bactericidal effect. Their high efficiency, which does not depend on the functional activity of the patient’s immune system, has made them an indispensable remedy for immune disorders and neutropenia. The following generations of aminoglycosides are distinguished:

Aminoglycosides are prescribed for infections of the respiratory system, sepsis, infective endocarditis, peritonitis, meningitis, cystitis, pyelonephritis, osteomyelitis and other pathologies. Among the side effects, toxic effects on the kidneys and hearing loss are of great importance.

Therefore, during the course of therapy, it is necessary to regularly conduct a biochemical blood test (creatinine, GCF, urea) and audiometry. For pregnant women, during lactation, patients with chronic kidney disease or on hemodialysis, aminoglycosides are prescribed only for health reasons.

Glycopeptides

Glycopeptide antibiotics have a broad-spectrum bactericidal effect. The best known of them are bleomycin and vancomycin. In clinical practice, glycopeptides are reserve drugs that are prescribed when other antibacterial agents are ineffective or the infectious agent is specific to them.

They are often combined with aminoglycosides, which increases the combined effect against Staphylococcus aureus, enterococcus and streptococcus. Glycopeptide antibiotics have no effect on mycobacteria and fungi.

This group of antibacterial agents is prescribed for endocarditis, sepsis, osteomyelitis, phlegmon, pneumonia (including complicated), abscess and pseudomembranous colitis. Glycopeptide antibiotics should not be used in case of renal failure, hypersensitivity to drugs, lactation, acoustic neuritis, pregnancy and lactation.

Lincosamides

Lincosamides include lincomycin and clindamycin. These drugs exhibit a bacteriostatic effect on gram-positive bacteria. I use them mainly in combination with aminoglycosides as a second-line treatment for severe patients.

Lincosamides are prescribed for aspiration pneumonia, osteomyelitis, diabetic foot, necrotizing fasciitis and other pathologies.

Quite often, while taking them, candidiasis infection, headache, allergic reactions and suppression of hematopoiesis develop.

Video

The video talks about how to quickly cure a cold, flu or acute respiratory viral infection. Opinion of an experienced doctor.

Broad-spectrum antibiotics are suitable for the treatment of infectious diseases of various organs of the digestive tract, respiratory and genitourinary systems. They differ in that the prescription of these drugs is advisable even before the pathogenic bacterium is accurately identified. Scientists are constantly striving to expand the list of these antibiotics. It is thanks to them that many diseases can be defeated in the early stages of clinical manifestations.

Antibiotics of the new generation extend their “broad” effect to a number of pathogens at once, be it gram-positive, gram-negative, anaerobic or atypical bacteria. However, there is a list of situations for which these groups are best suited:

1. Preoperative prophylaxis with antibiotics (administration of the drug intravenously 30-40 minutes before the start of surgery).
2. Treatment of infection until its specific pathogen is identified.
3. Treatment of an infection resistant to a certain group of antibacterial agents.
4. The presence of “superinfection” or “coinfection” (destruction of several microbes simultaneously present in the body).

It is more convenient to consider the names of antibiotics required to be prescribed in such cases as part of large groups.

Penicillins

These are common and cheap antibiotics, most of them are available in tablets and suspensions, so they are easy to use in outpatient practice (clinic, consultation centers).

Indicated for infection with gram-positive, gram-negative (gonococcus, meningococcus, E. coli, Haemophilus influenzae, Helicobacter pylori, salmonella) microbes. The drugs do not affect Proteus, mycoplasma, rickettsia. They have a bactericidal effect (complete destruction of cells).

Preparation	Trade name
Amoxicillin	Amoxicillin	Pills: 40-70
	Flemoxin Solutab	Pills: 0.5 g each twice a day, course of administration for 2 weeks. 400-530
		Capsules: similar regimen and duration of administration. 80-115
		Powder for suspension: Pour the powder from the bag into a glass of warm, clean water and stir. 45-90
Amoxicillin + clavulanic acid	Amoxiclav	Pills: 1 tablet (250+125 mg) three times a day or 1 tablet (500+125 mg) twice a day; take with food, course of treatment for 2 weeks. 225-385
		Powder for suspension: To calculate the dose of the medicine, use the attached tables. 130-280
	Flemoklav Solutab	Pills: 1 tablet (500+125 mg) three times a day or 1 tablet (875+125 mg) twice a day; do not chew, take at the beginning of meals, take the course for 2 weeks. 300-450
	Augmentin	Powder for suspension: Add 60 ml of clean water at room temperature to the bottle with the powder, wait 5 minutes, add the volume of water to the mark on the bottle, mix. 150-450
		Pills: 1 tablet (250+125 mg) three times a day, course of administration for 2 weeks. 250-380 rub.
Ampicillin	Ampicillin	Pills: 0.25-0.5 gr. every 6 hours 30-60 minutes before meals. 10-60
		Powder for suspension: 1.0-3.0 gr. per day in 4 doses; To prepare the mixture, add 62 ml of water to the bottle, the dosage of the mixture is carried out using the attached measuring spoon, take with warm water. 20-65
		Powder substance: 0.25-0.5 gr. every 4-6 hours intravenously/intramuscularly. 15-145

Respiratory fluoroquinolones

These strong antibiotics are also called 2nd generation fluoroquinolones. Unlike the early 1st generation (drugs - lomefloxacin, norfloxacin, ofloxacin, ciprofloxacin), the following drugs are active against the most comprehensive spectrum of microbes:

• gram-positive;
• atypical (mycobacterium tuberculosis, mycoplasma, chlamydia);
• anaerobic.

The substances are actively used in the second stage of treatment of pneumonia when penicillin antibiotics are ineffective. Bactericidal effect.

Representatives		Directions for use
Levofloxacin	Floracid 300-800	Pills: 0.5 gr. twice a day, without chewing.
	460-1000	Pills: 0.25 gr. (2 tablets) twice a day or 0.5 g. (1 tablet) 1 time per day with water, course 14 days.
Moxifloxacin	Moflaxia 320-350	Pills:
	220-380	Pills: 0.4 gr. x 1 time per day, without chewing, course 14 days.
Gatifloxacin	Gatispan 230-250	Pills: 0.4 gr. x 1 time per day, without chewing, course 10 days.
Sparfloxacin	200-250	Pills: 0.1-0.4 g. per day (depending on the type and severity of the infection).

Carbapenems

Modern “reserve” antibiotics, used only if there is no effect from other equally strong antimicrobial drugs. The range of action of carbapenems covers gram-positive and gram-negative bacteria, Pseudomonas aeruginosa.

Members of this group exhibit resistance to MRSA (methicillin-resistant Staphylococcus aureus). Meropenem is one of the best broad-spectrum antibiotics in the fight against meningococcal infection. The effect is bactericidal.

Representatives	Trade name, price (RUB)	Directions for use
Imipenem + cilastatin	4500-4800	2.0 gr. per day, administered in 4 injections intravenously/intramuscularly.
	Tsilapenem 340-380	Powder for injection solution: 1.0-2.0 gr. per day, administered intravenously in 3-4 infusions. To prepare the solution, add 100 ml of isotonic sodium chloride to the bottle and shake until smooth.
	Tiepenem 330-400	Powder for injection solution: 1.0-2.0 gr. per day, administered intravenously in 3-4 infusions. To prepare the solution, you need to add isotonic sodium chloride to the bottle in a ratio of 100 ml of sodium chloride per 0.5 g. drug, shake until completely homogeneous.
	Tsilaspen 340-360	Powder for injection solution: The method for preparing the solution and using it is similar to the above.
Meropenem	6000-11000	Powder for injection solution: 0.5 g each every 8 hours (pneumonia, genitourinary infections, skin infections); 1.0 g each every 8 hours (nosocomial pneumonia, sepsis); 2.0 gr. every 8 hours (meningitis). The medicine is administered intravenously slowly (within 5 minutes; the solution is prepared by adding 5 ml of sterile water per 250 mg of the drug) or intravenously drip (within 15-30 minutes; the solution is prepared by adding 50-200 ml of isotonic sodium chloride).
	Meropenem 300-350	Powder for injection solution: 0.5-2.0 gr. per day for intravenous administration; 0.5 g each every 8 hours for intramuscular administration.
Ertapenem	2300-2500	Lyophilisate for injection solution: 1.0 g each per day, administered in 1 injection intravenously/intramuscularly.
Doripenem	Doriprex 8000-21000	Powder for injection solution: 0.5 g each intravenously every 8 hours. To prepare the solution, the powder must be dissolved in 10 ml of isotonic sodium chloride solution, the resulting mixture should be added to a bag with 100 ml of isotonic sodium chloride solution or 5% glucose solution.

Aminoglycosides

The spectrum of drug activity includes:

• Staphylococci.
• Gram-negative microbes.
• Pathogens of specific infections - plague, brucellosis, tularemia.
• Pseudomonas aeruginosa.
• Acinetobacter.
• Mycobacterium tuberculosis.

At the same time, for the 1st generation the main indication is tuberculosis infection, for the 2nd and 3rd generations – Pseudomonas aeruginosa infection. They have a bactericidal effect.

1st generation:

Representatives	Trade name, price (RUB)	Directions for use
Kanamycin	Kanamycin 12-650	Powder for injection solution: 1.0-1.5 gr. for 2-3 injections intravenously (a single dose (0.5 g) is dissolved in 200 ml of a 5% dextrose solution).
	Kanamycin sulfate 605-750	Powder substance: For intramuscular administration 0.5 g./1.0 g. dissolve in 2/4 ml of sterile water or 0.25% novocaine. For intravenous administration 0.5 g. dissolve in 200 ml of saline or 5% glucose solution. For tuberculosis – 1.0 g. x 1 time per day. For other infections - 0.5 g. every 8-12 hours.
Streptomycin	Streptomycin sulfate 20-500	Powder substance: For intramuscular administration - 0.5-1.0 g. per day. For intratracheal/aerosol administration – 0.5-1.0 g. x 2-3 times every 7 days.
	Streptomycin 8-430	Powder for injection solution: 0.5–1.0 g each. x 2 times a day intramuscularly. To prepare the solution, use sterile water/saline solution/0.25% novocaine. Calculation: per 1.0 g. medications - 4 ml of solvent.
Neomycin	Neomycin 360-385	External aerosol: on the affected areas of the skin, shake well and place the balloon at a distance of 15-20 cm, apply for 3 seconds; Repeat application 1-3 times a day.

2nd generation:

Representatives	Trade name	Method of application, price (rub.)
Gentamicin	Gentamicin sulfate	Powder substance: up to 1.2 mg per 1 kg of body weight per day for 2-3 injections (urinary infections); 2.4-3.3 mg per 1 kg of body weight per day for 2-3 injections (severe infections, sepsis). Administer the medicine intramuscularly/intravenously. 40-250
	Gentamicin	Solution for injection: 0.003-0.005 gr. per 1 kg of weight for 2-4 injections, administered intravenously/intramuscularly. 45-120
		Eye drops: 1-2 drops every 1-4 hours, retracting the lower eyelid. 160-200
		Ointment: on the affected areas of the skin, 3-4 applications per day. 90-150
Tobramycin	Tobrex	Eye drops: 1-2 drops, pulling back the lower eyelid, every 4 hours; for severe eye infections - 2 drops every hour. 170-220
	Bramitob	Solution for inhalation: 1 ampoule of medication (0.3 g) every 12 hours, administered by inhalation using a nebulizer, course 28 days. 19000-33000
	Tobriss	Eye drops: 1 drop, pulling back the lower eyelid, 2 times a day (morning and evening); for severe eye infections - 1 drop x 4 times a day. 140-200

3rd generation:

Representatives	Trade name, price (RUB)	Directions for use
Netilmicin	Nettatsin 420-500	Eye drops: 1-2 drops, pulling back the lower eyelid, 3 times a day.
	Vero-Netilmicin 160-200	Solution for injection: 4-6 mg per 1 kg of body weight per day intravenously/intramuscularly; for severe infections, the daily dose can be increased to 7.5 mg per 1 kg.
Amikacin	Amikacin 50-1600	Solution for infusion: 0.01-0.015 gr. per 1 kg of body weight per day for 2-3 injections, administered intramuscularly/intravenously (stream, drip).
	Amikacin sulfate 50-150	Powder substance: 0.005 gr. per 1 kg of weight every 8 hours or 0.0075 g. per 1 kg of body weight every 12 hours, administered intramuscularly/intravenously.
Spectinomycin	300-450	Powder for making suspension: 2.0 gr. (5 ml)/4.0 g. (10 ml) deep intramuscularly into the upper outer part of the buttock. To prepare the suspension, you need to add 3.2 ml of sterile water to the vial. Suspension for single use, storage is prohibited.
Framycetin	340-380	Nasal spray: 1 injection into each nasal passage x 4-6 times a day, course no more than 10 days.

4th generation:

Glycopeptides

They are also confidently designated as new generation broad-spectrum antibiotics. Their bactericidal influence includes:

• Gram-positive bacteria, including MRSA and MRSE (methicillin-resistant Staphylococcus epidermidis).
• Enterococci.
• Anaerobes, including Clostridium difficile, the causative agent of pseudomembranous colitis.

Vancomycin stands out as one of the last antibiotics most commonly prescribed in hospitals. The effect of the drugs is bactericidal, only on enterococci and streptococci - bacteriostatic (“inhibition” of bacterial activity).

Representatives	Trade name, price (RUB)	Directions for use
Vancomycin	600-700	2.0 gr. per day strictly intravenously (0.5 g every 6 hours or 1.0 g every 12 hours).
	Vancomycin 180-360	Powder for infusion solution: 0.5 g each every 6 hours or 1.0 g. every 12 hours.
Teicoplanin	Teicoplanin 400-450	Lyophilisate for infusion solution: 0.4 g each every 12 hours intravenously/intramuscularly.
Telavantzin	8000-10000	Lyophilisate for infusion solution: 10 mg per 1 kg of body weight every 24 hours, administered intravenously (at least an hour).

Macrolides

Slightly toxic drugs that have a bactericidal effect on:

• gram-positive bacteria (streptococci, staphylococci, mycobacteria);
• gram-negative bacilli (enterobacteriaceae, Helicobacter pylori, Haemophilus influenzae);
• intracellular microorganisms (moraxella, legionella, mycoplasma, chlamydia).

14-member:

Representatives	Trade name	Method of application, price (rub.)
Clarithromycin	Klacid	Pills : 0.5 g each. twice a day, taken for 2 weeks. 510-800
		Granules for preparing suspension : to prepare the mixture, pour warm water up to the mark on the bottle, stir, take 2 times a day. 355-450
		Solution for infusion : 0.5 g each. twice a day. 650-700
	Fromilid	Pills : 0.5 g twice a day, taken for 2 weeks. 290-680
	Clarithrosin	Pills : 0.25 g each. twice a day, taken for 2 weeks. 100-150
Roxithromycin	RoxyHEXAL	Pills : 0.15 g each. twice a day or 0.3 g. in one dose, course of treatment 10 days. 110-170
	Esparoxy	Pills : 0.15 g each. twice a day 15 minutes before meals or 0.3 g. once, the course of administration is 10 days. 330-350
	Rulid	Pills : 0.15 g each. twice a day, course of treatment is 10 days. 1000-1400
Oleandomycin	Oleandomycin phosphate	Substance-powder . Practically not used at present. 170-200
Erythromycin	Erythromycin	Pills : 0.2-0.4 g each. four times a day before or after meals, washed down with water, course of administration is 7-10 days. 70-90
		Lyophilisate for the preparation of solution for infusion : 0.2 g, diluted with a solvent, 3 times a day. The maximum course of treatment is 2 weeks. 550-590
		Eye ointment : place behind the lower eyelid three times a day, course of use is 14 days. 70-140
		External ointment : apply a small layer to the affected areas of the skin 2-3 times a day. 80-100

15-member:

Representatives	Trade name	Method of application, price (rub.)
Azithromycin	Sumamed	Capsules : 0.5 g each. x 1 time per day before or 2 hours after meals. 450-550
		Powder for oral suspension : add 11 ml of water to the bottle, shake, take 1 time per day before or after meals. 220-570
		Pills : 0.5 g each. x 1 time per day before or after meals. 250-580
	Azitral	Capsules : 0.25-0.5 g each. x 1 time per day before or after meals. 280-340
	Azitrox	Capsules : 0.25-0.5 g each. x 1 time per day. 280-330
		Powder for oral suspension : add 9.5 ml of water to the bottle, shake, orally 2 times a day. 130-370

16-member:

Representatives	Trade name	Method of application, price (rub.)
Midecamycin	Macropen	Pills : 0.4 g each. three times a day, course of administration for 2 weeks. 250-340
Josamycin	Vilprafen	Pills : 0.5 g each. twice a day, without chewing, with water. 530-620
	Vilprafen solutab	Pills : 0.5 g each. x twice a day, without chewing or dissolved in 20 ml of water. 650-750
Spiramycin	Spiramycin-vero	Pills : 2-3 tablets (3 million IU) for 2-3 doses per day. 220-1750
	Rovamycin	Pills : 2-3 tablets (3 million IU) or 5-6 tablets (6-9 million IU) for 2-3 doses per day. 1010-1700

Cephalosporins

The wide spectrum of influence includes representatives of the 3rd and 5th generations of cephalosporins. A destructive bactericidal effect was observed against gram-negative (enterobacteriaceae, hemophilus influenzae, gono- and meningococcus, Klebsiella, moraxella, protea), anaerobic (peptococci, peptostreptococci, bacteroides, clostridia) and gram-positive microbes.

3rd generation:

Parenteral:

Representatives	Trade name	Method of application, price (rub.)
Cefotaxime	Claforan	: 0.5-2.0 gr. x 1 time per day intramuscularly or intravenously slowly. 120-150
	Cephosin	Powder for injection solution : 1.0 g each. every 8-12 hours intramuscularly, intravenously slowly/drip. 50-75
Ceftazidime	Fortum	Powder for injection solution : 1.0-6.0 gr. x 1 time per day for 2-3 intravenous/intramuscular infusions. 450-530
	Ceftidine	Powder for injection solution : 1.0-6.0 gr. x 1 time per day intravenously/intramuscularly. 155-200
Ceftriaxone	Ceftriaxone	Powder for injection solution : 1.0-2.0 gr. x 1 time per day intramuscularly/intravenously. 30-900
	Azaran	Powder for injection solution : 1.0 gr. dissolve in 3.5 ml of 1% solution of lidocaine hydrochloride, intramuscular injections 1 time per day. 2350-2600
Cefoperazone	Cephobid	Powder for injection solution : 2.0-4.0 gr. per day for 2 intramuscular injections. 250-300
	Tsefpar	Powder for injection solution : 2.0-4.0 gr. every 12 hours intravenously/intramuscularly. 35-105

Oral:

5th generation (parenteral):

Antibiotics for children

Prescribing broad-spectrum antibiotics for children is possible, however, not in all cases. All dosages for children of different ages are usually calculated per 1 kg of body weight and do not exceed adult doses. To understand which particular drug belongs to the list of children's antibiotics with a wide coverage of pathogenic microorganisms, you need to carefully study the attached instructions. We must not forget that each antibiotic has its own age-related characteristics.

Broad-spectrum antibiotics are indispensable medicines for hospitals of any level and profile of medical services. Ease of use and high probability of a beneficial effect make them invaluable in the treatment of a wide variety of infections. To maintain the susceptibility of microbes to these drugs, do not start taking them on your own without consulting a doctor and adhere to the correct dosage regimen.

Antibiotics are a group of medications that have a damaging or destructive effect on bacteria that cause infectious diseases. This type of medicine is not used as antiviral drugs. Depending on the ability to destroy or inhibit certain microorganisms, there are different groups of antibiotics. In addition, this type of medicine can be classified according to its origin, the nature of its effect on bacterial cells and some other characteristics.

General description

Antibiotics belong to the group of antiseptic biological drugs. They are waste products of moldy and radiant fungi, as well as some types of bacteria. Currently, more than 6,000 natural antibiotics are known. In addition, there are tens of thousands of synthetic and semi-synthetic ones. But only about 50 such drugs are used in practice.

Main groups

All such drugs that currently exist are divided into three large groups:

• antibacterial;
• antifungal;
• antitumor.

In addition, according to the direction of action, this type of medicine is divided into:

• active against gram-positive bacteria;
• anti-tuberculosis;
• active against both gram-positive and gram-negative bacteria;
• antifungal;
• destroying helminths;
• antitumor.

Classification by type of effect on microbial cells

In this regard, there are two main groups of antibiotics:

• Bacteriostatic. Medicines of this type suppress the development and reproduction of bacteria.
• Bactericidal. When using drugs from this group, existing microorganisms are destroyed.

Types by chemical composition

The classification of antibiotics into groups in this case is as follows:

• Penicillins. This is the oldest group with which, in fact, the development of this direction of drug treatment began.
• Cephalosporins. This group is used very widely and is characterized by a high degree of resistance to the destructive action of β-lactamases. This is the name given to special enzymes secreted by pathogenic microorganisms.
• Macrolides. These are the safest and quite effective antibiotics.
• Tetracyclines. These drugs are used mainly to treat the respiratory and urinary tract.
• Aminoglycosides. They have a very wide spectrum of action.
• Fluoroquinolones. Low-toxic bactericidal preparations.

These antibiotics are used most often in modern medicine. Besides them, there are some others: glycopeptides, polyenes, etc.

Antibiotics of the penicillin group

Medicines of this type are the fundamental basis of absolutely any antimicrobial treatment. At the beginning of the last century, no one knew about antibiotics. In 1929, the Englishman A. Fleming discovered the very first such drug - penicillin. The principle of action of drugs in this group is based on the suppression of protein synthesis in the cell walls of the pathogen.

At the moment, there are only three main groups of penicillin antibiotics:

• biosynthetic;
• semi-synthetic;
• semi-synthetic broad spectrum.

The first type is used mainly for the treatment of diseases caused by staphylococci, streptococci, meningococci, etc. Such antibiotics can be prescribed, for example, for diseases such as pneumonia, infectious skin lesions, gonorrhea, syphilis, gas gangrene, etc. .

Semi-synthetic antibiotics of the penicillin group are most often used to treat severe staphylococcal infections. Such drugs are less active against certain types of bacteria (for example, gonococci and meningococci) than biosynthetic ones. Therefore, before their appointment, procedures such as isolation and precise identification of the pathogen are usually performed.

Broad-spectrum semi-synthetic penicillins are usually used if traditional antibiotics (chloramphenicol, tetracycline, etc.) do not help the patient. This variety includes, for example, the fairly frequently used amoxicillin group of antibiotics.

Four generations of penicillins

In medical In practice today, four types of antibiotics from the penicillin group are used:

• The first generation is medicines of natural origin. This type of drug has a very narrow range of applications and is not very resistant to penicillinases (β-lactamases).
• The second and third generations are antibiotics that are much less susceptible to the destructive enzymes of bacteria, and therefore more effective. Treatment with their use can take place in a fairly short time.
• The fourth generation includes broad-spectrum antibiotics of the penicillin group.

The most famous penicillins are the semisynthetic drugs Ampicillin, Carbenicillin, Azocillin, as well as the biosynthetic Benzylpenicillin and its durant forms (bicillins).

Side effects

Although antibiotics in this group are low-toxic drugs, they, along with their beneficial effects, can also have a negative effect on the human body. Side effects when using them are as follows:

• itching and skin rash;
• allergic reactions;
• dysbacteriosis;
• nausea and diarrhea;
• stomatitis.

Penicillins cannot be used simultaneously with antibiotics of another group - macrolides.

Amoxicillin group of antibiotics

This type of antimicrobial drug belongs to the penicillins and is used to treat diseases caused by infection with both gram-positive and gram-negative bacteria. Such medications can be used to treat both children and adults. Most often, amoxicillin-based antibiotics are prescribed for respiratory tract infections and various gastrointestinal diseases. They are also taken for diseases of the genitourinary system.

The amoxicillin group of antibiotics is also used for various infections of soft tissues and skin. These drugs can cause the same side effects as other penicillins.

Group of cephalosporins

The action of drugs in this group is also bacteriostatic. Their advantage over penicillins is their good resistance to β-lactamases. Antibiotics of the cephalosporin group are classified into two main groups:

• taken parenterally (bypassing the gastrointestinal tract);
• taken orally.

In addition, cephalosporins are classified into:

• First generation drugs. They have a narrow spectrum of action and have virtually no effect on gram-negative bacteria. Moreover, such drugs are successfully used in the treatment of diseases caused by streptococci.
• Second generation cephalosporins. More effective against gram-negative bacteria. They are active against staphylococci and streptococci, but have virtually no effect on etherococci.
• Third and fourth generation drugs. This group of drugs is very resistant to the action of β-lactamases.

The main disadvantage of drugs such as cephalosporin antibiotics is that when taken orally they are very irritating to the gastrointestinal mucosa (except for the drug Cephalexin). The advantage of drugs of this type is that the number of side effects caused is much smaller compared to penicillins. The drugs most often used in medical practice are Cefalotin and Cefazolin.

Negative effects of cephalosporins on the body

Side effects that sometimes occur when taking antibiotics of this series include:

• negative effects on the kidneys;
• violation of hematopoietic function;
• various types of allergies;
• negative impact on the gastrointestinal tract.

Antibiotics of the macrolide group

Among other things, antibiotics are classified according to the degree of selectivity of action. Some are capable of negatively affecting only the cells of the pathogen, without affecting human tissue in any way. Others may have a toxic effect on the patient's body. Macrolide group drugs are considered the safest in this regard.

There are two main groups of antibiotics of this variety:

• natural;
• semi-synthetic.

The main advantages of macrolides include the highest efficiency of bacteriostatic effects. They are especially active against staphylococci and streptococci. Among other things, macrolides do not negatively affect the gastrointestinal mucosa, and therefore are often available in tablets. All antibiotics affect the human immune system to one degree or another. Some types are depressing, some are beneficial. Antibiotics of the macrolide group have a positive immunomodulatory effect on the patient's body.

Popular macrolides are Azithromycin, Sumamed, Erythromycin, Fuzidin, etc.

Antibiotics of the tetracycline group

Medicines of this type were first discovered in the 40s of the last century. The very first tetracycline drug was isolated by B. Duggar in 1945. It was called "Chlortetracycline" and was less toxic than other antibiotics existing at that time. In addition, it also turned out to be very effective in terms of influencing the pathogens of a huge number of very dangerous diseases (for example, typhoid).

Tetracyclines are considered somewhat less toxic than penicillins, but have more negative effects on the body than macrolide antibiotics. Therefore, at the moment they are actively being replaced by the latter.

Today, the drug “Chlortetracycline”, discovered in the last century, oddly enough, is very actively used not in medicine, but in agriculture. The fact is that this drug can accelerate the growth of animals taking it almost twice. The substance has such an effect because when it enters the animal’s intestines it begins to actively interact with the microflora present in it.

In addition to the drug “Tetracycline” itself, medications such as “Metacycline”, “Vibramycin”, “Doxycycline”, etc. are often used in medical practice.

Side effects caused by tetracycline antibiotics

The refusal to widely use drugs of this type in medicine is primarily due to the fact that they can have not only beneficial but also negative effects on the human body. For example, when taken for a long time, antibiotics of the tetracycline group can disrupt the development of bones and teeth in children. In addition, by interacting with the human intestinal microflora (if used incorrectly), such drugs often provoke the development of fungal diseases. Some researchers even argue that tetracyclines can have a depressing effect on the male reproductive system.

Antibiotics of the aminoglycoside group

Preparations of this type have a bactericidal effect on the pathogen. Aminoglycosides, like penicillins and tetracyclines, are one of the oldest groups of antibiotics. They were opened in 1943. In subsequent years, drugs of this type, in particular Streptomycin, were widely used to treat tuberculosis. In particular, aminoglycosides are effective against gram-negative aerobic bacteria and staphylococci. Among other things, some drugs in this series are also active against protozoa. Since aminoglycosides are much more toxic than other antibiotics, they are prescribed only for severe illnesses. They are effective, for example, in sepsis, tuberculosis, severe forms of paranephritis, abdominal abscesses, etc.

Very often, doctors prescribe aminoglycosides such as Neomycin, Kanamycin, Gentamicin, etc.

Fluoroquinolone group drugs

Most drugs of this type of antibiotic have a bactericidal effect on the pathogen. Their advantages include, first of all, the highest activity against a huge number of microbes. Like aminoglycosides, fluoroquinolones can be used to treat serious diseases. However, they do not have such a negative effect on the human body as the first ones. There are antibiotics from the fluoroquinolone group:

• First generation. This type is used mainly for inpatient treatment of patients. First generation fluoroquinolones are used for infections of the liver, biliary tract, pneumonia, etc.
• Second generation. These drugs, unlike the first ones, are very active against gram-positive bacteria. Therefore, they are also prescribed for treatment without hospitalization. Second-generation fluoroquinolones are very widely used for sexually transmitted diseases.

Popular drugs in this group are Norfloxacin, Levofloxacin, Gemifloxacin, etc.

So, we found out which group antibiotics belong to, and figured out exactly how they are classified. Because most of these drugs can cause side effects, they should only be used as directed by your doctor.

Today even primary school children know what antibiotics are. However, the term “broad-spectrum antibiotics” sometimes confuses even adults and raises many questions. How wide is the spectrum? What antibiotics are these? And, yes, it seems that there are also narrow-spectrum drugs that may not help?

The most surprising thing is that even the all-knowing Internet often cannot help and dispel the fog of doubt. In this article we will try to slowly and methodically figure out what kind of broad-spectrum antibiotics they are, what bacteria they act on, as well as when, how and how many times a day they are used.

The diverse world of bacteria

And we will start from the very beginning - with microbes. Bacteria make up the majority of prokaryotes - single-celled living organisms without a clearly defined nucleus. It was bacteria that first populated the lonely Earth millions of years ago. They live everywhere: in soil, water, acidic hot springs and radioactive waste. Descriptions of about 10 thousand species of bacteria are known, but it is estimated that their number reaches a million.

And of course, bacteria live in the bodies of plants, animals and humans. Relationships between lower unicellular organisms and higher multicellular organisms can be different - both friendly, mutually beneficial for partners, and openly hostile.

A person cannot exist without “good”, correct bacteria that form the microflora. However, along with valuable bifidobacteria and lactobacilli, microbes that cause a wide variety of diseases enter our bodies.

The microflora also includes so-called opportunistic microorganisms. Under favorable conditions, they do no harm, but as soon as our immunity decreases, these yesterday’s friends turn into vicious enemies. In order to somehow understand the host of bacteria, doctors proposed classifying them.

Gram- and Gram+: deciphering the puzzle

The most famous separation of microbes is very often mentioned in pharmacies, clinics, and in drug annotations. And just as often, the living average patient does not understand what we are actually talking about. Let's figure out together what these mysterious expressions gram+ and gram- mean, without which not a single description of the action of antibiotics is complete?

Back in 1885, the Dane Hans Gram decided to stain sections of lung tissue to make the bacteria more visible. The scientist found that the causative agent of typhus, Salmonella typhi, did not change color, while other microorganisms were exposed to the chemical.

The most famous classification today is based on the ability of bacteria to stain according to Gram. A group of bacteria that do not change color are called gram-negative. The second category is called gram-positive, that is, Gram-staining microorganisms.

Gram-positive and gram-negative pathogens: who is who?

Another, no less important classification of antibiotics breaks down drugs according to their spectrum of action and structure. Again, to understand the complex paragraphs of instructions explaining the spectrum of activity and belonging to a specific group, you need to get to know the microbes better.

Gram-positive bacteria include cocci, that is, spherical microorganisms, including numerous families of staphylococci and streptococci. In addition, clostridia, corynebacteria, listeria, and enterococci belong to this group. Gram-positive pathogens most often cause infectious diseases of the nasopharynx, respiratory tract, ear, as well as inflammatory processes of the eye.

Gram-negative bacteria are a not so numerous group of microorganisms that mainly cause intestinal infections, as well as diseases of the genitourinary tract. Much less frequently, gram-negative pathogens are responsible for respiratory tract pathologies. These include Escherichia coli, Salmonella, Shigella (the causative agent of diphtheria), Pseudomonas, Moraxella, Legionella, Klebsiella, Proteus.

Among gram-negative microorganisms there are also causative agents of severe hospital infections. These microbes are difficult to treat - in hospital conditions they develop special resistance to most antibiotics. Therefore, special, often intramuscular or intravenous, broad-spectrum antibiotics are used to treat such infectious diseases.

Empirical therapy is based on this “separation” of gram-negative and gram-positive bacteria, which involves selecting an antibiotic without prior culture, that is, practically “by eye.” As practice shows, in the case of “standard” diseases, this approach to choosing a drug is completely justified. If the doctor has doubts about whether the pathogen belongs to one group or another, prescribing broad-spectrum antibiotics will help “get the ball in the air.”

Broad spectrum antibiotics: the whole army is at gunpoint

So, we come to the most interesting part. Broad-spectrum antibiotics are a universal antibacterial medicine. Whatever the pathogen is the source of the disease, broad-spectrum antibacterial agents will have a bactericidal effect and defeat the microbe.

As a rule, broad-spectrum drugs are used when:

• treatment is prescribed empirically, that is, based on clinical symptoms. When selecting an antibiotic empirically, time and money are not wasted on identifying the pathogen. The microbe that caused the disease will forever remain unknown. This approach is appropriate in the case of common infections, as well as fast-acting dangerous diseases. For example, with purulent meningitis, death can be predicted literally within a few hours if antibiotic therapy is not started immediately after the first signs of the disease;
• pathogens are resistant to narrow-spectrum antibiotics;
• a superinfection has been diagnosed, in which several types of bacteria are the culprits of the disease;
• prevention of infection after surgical interventions is carried out.

List of broad-spectrum antibiotics

Let's try to name by name those antibacterial drugs that have a wide spectrum of activity:

• antibiotics of the penicillin group: , Ampicillin, Ticarcycline;
• antibiotics of the tetracycline group: Tetracycline;
• fluoroquinolones: Levofloxacin, Gatifloxacin, Moxifloxacin, Ciprofloxacin;
• Aminoglycosides: Streptomycin;
• Amphenicols: Chloramphenicol (Levomycetin);
• Carbapenems: Imipenem, Meropenem, Ertapenem.

As you can see, the list of broad-spectrum antibiotics is not very large. And we will begin a detailed description of drugs with probably the most popular group - penicillin antibiotics.

Penicillins - drugs that people know and love

With the discovery of an antibiotic of this particular group - Benzylpenicillin - doctors realized that microbes could be defeated. Despite its venerable age, benzylpenicillin is still used today, and in some cases it is a first-line drug. However, broad-spectrum agents include other, newer penicillin antibiotics, which can be divided into two groups:

• drugs for parenteral (injection) and enteral administration, which withstand the acidic environment of the stomach;
• injection antibiotics that do not withstand the action of hydrochloric acid - Carbenicillin, Ticarcillin.

Ampicillin and Amoxicillin are popular broad-spectrum penicillins

Ampicillin and Amoxicillin occupy a special place of honor among penicillin antibiotics. The spectrum and effect on the human body of these two antibiotics are almost the same. Among the microorganisms sensitive to Ampicillin and Amoxicillin, the most well-known infectious agents are:

• gram-positive bacteria: staphylococci and streptococci, enterococci, listeria;
• gram-negative bacteria: gonorrhea pathogen Neisseria gonorrhoeae, E. coli, Shigella, salmonella, Haemophilus influenzae, whooping cough pathogen Bordetella pertussis.

With an identical spectrum, Ampicillin and Amoxicillin differ significantly in pharmacokinetic properties.

Ampicillin

Ampicillin was synthesized in the early 60s of the last century. The drug immediately won the hearts of doctors: its spectrum of action compared favorably with the antibiotics of the 50s, to which persistence, that is, addiction, had already developed.

However, Ampicillin has significant disadvantages - low bioavailability and short half-life. The antibiotic is absorbed by only 35–50%, and the half-life is several hours. In this regard, the course of treatment with Ampicillin is quite intensive: tablets should be taken at a dose of 250–500 mg four times a day.

A feature of Ampicillin, which is considered an advantage over Amoxicillin, is the possibility of parenteral administration of the drug. The antibiotic is produced in the form of a lyophilized powder, from which a solution is prepared before administration. Ampicillin is prescribed 250–1000 mg every 4–6 hours intramuscularly or intravenously.

Amoxicillin is slightly younger than its predecessor - it went on sale in the 70s of the 20th century. Nevertheless, this antibiotic is still one of the most popular and effective broad-spectrum drugs, including for children. And this became possible thanks to the undoubted advantages of the drug.

These include the high bioavailability of Amoxicillin tablets, which reaches 75–90%, against the background of a fairly long half-life. Moreover, the degree of absorption does not depend on food intake. The drug has a high degree of affinity for the tissues of the respiratory tract: the concentration of Amoxicillin in the lungs and bronchi is almost twice as high as in other tissues and blood. It is not surprising that Amoxicillin is considered the drug of choice for uncomplicated forms of bacterial bronchitis and pneumonia.

In addition, the medicine is indicated for sore throat, infections of the urinary and reproductive tract, and infectious skin diseases. Amoxicillin is a component of eradication therapy for gastric and duodenal ulcers.

The drug is taken orally at a dosage of 250–1000 mg twice a day for 5–10 days.

Broad-spectrum parenteral penicillins

Penicillins, which are used for parenteral administration, differ from the known Ampicillin and Amoxicillin in their additional activity against Pseudomonas aeruginosa. This microorganism causes soft tissue infections - abscesses, purulent wounds. Pseudomonas also act as causative agents of cystitis - inflammation of the bladder, as well as inflammation of the intestines - enteritis.

In addition, broad-spectrum parenteral penicillin antibiotics have bactericidal and bacteriostatic effects against:

• gram-positive microorganisms: staphylococci, streptococci (except for strains that form penicillinase), as well as enterobacteria;
• gram-negative microorganisms: Proteus, Salmonella, Shigella, Escherichia coli, Haemophilus influenzae and others.

Broad-spectrum parenteral penicillins include Carbenicillin, Ticarcillin, Carfecillin, Piperacillin and others.

Let's look at the most well-known antibiotics - Carbenicillin, Ticarcillin and Piperacillin.

Carbenicillin

In medicine, carbenicillin disodium salt is used, which is a white powder that is dissolved before use.

Carbenicillin is indicated for infections of the abdominal cavity, including peritonitis, the genitourinary system, the respiratory tract, as well as meningitis, sepsis, infections of bone tissue, and skin.

The drug is administered intramuscularly, and in severe cases intravenously.

Ticarcillin

Unprotected Ticarcillin is prescribed for severe infections caused by strains of bacteria that do not produce penicillinase: sepsis, septicemia, peritonitis, postoperative infections. The antibiotic is also used for gynecological infections, including endometritis, as well as infections of the respiratory tract, ENT organs, and skin. In addition, Ticarcillin is used for infectious diseases in patients with a reduced immune response.

Piperacillin

Piperacillin is mainly used together with the beta-lactamase inhibitor tazobactam. However, if it is determined that the causative agent of the disease does not produce penicillinase, an unprotected antibiotic may be prescribed.

Indications for the use of Piperacillin include severe purulent-inflammatory infections of the genitourinary system, abdominal cavity, respiratory and ENT organs, skin, bones and joints, as well as sepsis, meningitis, postoperative infections and other diseases.

Protected broad-spectrum penicillins: antibiotics to fight resistance!

Amoxicillin and Ampicillin are far from omnipotent. Both drugs are destroyed by beta-lactamases, which are produced by some strains of bacteria. Such “harmful” pathogens include many types of staphylococcus, including Staphylococcus aureus, Haemophilus influenzae, Moraxella, Escherichia coli, Klebsiella and other bacteria.

If the infection is caused by beta-lactamase-producing pathogens, Amoxicillin, Ampicillin and some other antibiotics are simply destroyed without causing any harm to the bacteria. Scientists found a way out of the situation by creating complexes of penicillin antibiotics with substances that inhibit beta-lactamases. In addition to the most famous clavulanic acid, inhibitors of destructive enzymes include sulbactam and tazobactam.

Protected antibiotics can effectively fight infection that the fragile and lonely penicillin cannot. Therefore, combination drugs are often the drugs of choice for a wide variety of diseases caused by bacterial infection, including hospital-acquired ones. The leading places in this list of broad-spectrum antibiotics are occupied by two or three drugs, and some injectable drugs used in hospitals remain behind the scenes. Paying tribute to the spectrum of each combined penicillin, we will open the veil of secrecy and list these, of course, worthy drugs.

Amoxicillin + clavulanic acid. The most famous combined broad-spectrum antibiotic, which has dozens of generics: Augmentin, Amoxiclav, Flemoclav. There are both oral and injectable forms of this antibiotic.