How do antibiotics work?

By Ben Harris
Updated 2023-10-31 04:25:22 | Published 2018-07-26 16:33:25
  • Blog
    • Add to favorites
    • Join our community in exploring insightful stories, tips, and experiences that inspire and inform. The iMedix Blog is your go-to destination for connecting with others and enriching your health knowledge.

    • Questions:
      372
Antibiotics

Antibiotics for clinical use are usually divided into object drugs and relief medications. Antibiotics of choices are drugs that have an optimal benefit-risk profile and from which the treatment is initiated before determining the sensitivity of the microorganisms that caused the disease.

Reserve antibiotics are used in case of resistance of microorganisms or when the patient is intolerant to drugs of choices. Reserve antibiotics usually have less activity. They have more pronounced side effects, greater toxicity. Also, resistance to such drugs develops rapidly.

Did you know such a simple question: how long do antibiotics stay in your system?

Antibiotics by level of efficiency in the anti-bacterial therapy are divided into I, II, III, IV generations. Generations of antibiotics differ among themselves in the effectiveness of exposure to bacterial cells. In clinical practice, the interval of appearance of new class of antibiotics is usually every 10 years. First of all, this is due to the fact that during this time resistant microorganism strains are produced for old antibiotics. However, this separation of antibiotics into generations is not always associated with the lead time of new drugs into the treatment practice.

The action of antibiotic at the cellular level can be:

  • Bacteriostatic (antibiotic blocks the replication and division of cells and does not cause their death. Cells retain the ability to grow and multiply if the antibiotic is removed);
  • Bactericidal (antibiotic kills bacterial cells).

Bactericidal antibiotic has germ-kill effect since it acts on subcellular structures irreversibly disrupting their integrity and/or function. In this case, the antibiotic, because of its high affinity, binds to the enzyme or cellular structures necessary to maintain the viability of the cell, which is practically irreversible. In this case, antibiotic binds to the enzyme or subcellular structures which is necessary to maintain the viability of the cell and almost irreversibly kills them.

Bacteriostatic antibiotics (such as amoxil, zithromax, cipro, flagyl, levofloxacin) also interact with subcellular structures, but they have less effect on them. Bacterial cells become active again when the patient stops to take these antibiotics.

The cell wall of most bacterial cells is thin, elastic and rigid. It protects the microbial cell from external influences and determines the shape of the microorganism.

Simultaneously, the cell wall maintains the constancy of the internal environment and protects the cell from destruction at high intracellular osmotic pressure.

Through the cell wall there is transport of nutrients into the cell and the release of metabolites. Structures and compositions of cell wall elements are different. This made it possible to differentiate microorganisms into gram-positive and gram-negative microorganisms.

Antibiotics by the mechanism of action are divided into:

  • inhibitors of synthesis of microbial wall components or activators of enzymes that destroy cell wall (penicillins, cephalosporins, monobactams, carbapenems);
  • drugs which disturbing the structure and function of cytoplasmic membranes of bacterial cells (polymyxins, polyene antibiotics);
    inhibitors of RNA synthesis at the level of RNA polymerase (rifamycins, griseofulvin);
  • inhibitors of protein production at the level of ribosomes (bactericidal – aminoglycosides; bacteriostatic – chloramphenicol, tetracycline, fucidin, lincomycin, macrolides).
User-thumb
Ben Harris is verified user for iMedix

  • Antibiotics
    • Add to favorites
    • Antibiotics are drugs killing bacteria, which are the root cause of the majority of infectious diseases development. Antibiotics kill bacteria but do not affect viruses.

    • Questions:
  • Drugs
    • Add to favorites
    • Here we have gathered useful information containing diseases and medications description. We did our best to provide you with answers to most frequently asked questions. Our experts and partners provide us with the necessary support being available on-line 24/7 to provide all the necessary clarifications.

    • Questions: