Antibiotics Flashcards
Define antiinfectives:
Substances used for treatment of infectious diseases
Division of antimicrobials:
- Antibacterics - against bacteria
- Antimycotics - against moulds and yiests
- Antivirotics - against viruses
Division of antibacterics according to chemical structure:
I. Antibiotics
II. Chemotherapeutics
Division of chemotherapeutics:
a) Sulphanomides
b) Quinolones
c) Nitrofurans
What are antibiotics made from, and how do they work?
- they are products of metabolism of microorganisms
- kill or stop the growing of other microorganisms
Classify antibiotics according to their effect on microorganisms:
- Bacteriostatic
- Bactericidal
Bacteriostatic antibiotics function:
- suppress the growth of bacteria
- used in acute diseases
Examples of bacteriostatic antibiotics:
Macrolides, Tetracyclines, Amfenicols, Diterpens, Lincosamides and Sulphanomides
Bactericidal antibiotics function:
- kill bacteria
- used in chronic diseases
Examples of bactericidal antibiotics:
Penicillins, Cephalosporins, Monobactams, Carbapenems, Polyptides, Glycopeptides, Ansamycins and Quinolones
Classification of antibiotics according to mechanisms of action: 4
- Cell wall synthesis inhibitors
- Permeability of cell membrane
- Protein synthesis inhibitors
- Nucleic acids synthesis inhibitors
Name examples of cell wall synthesis inhibitors:
b-lactams and glycopeptides
Name examples of antibiotics affecting permeability of cell membrane:
polyens, polymyxin, nystatin and amphotericin B
Name examples of protein synthesis inhibitors:
tetracyclines, amphenicols, aminoglycosides, macrolides, pleuromutilins, lincosamides and steroid substances (fusidic acid)
Name examples of nucleic acids synthesis inhibitors:
rifamycins and griseofulvin
Classify antibiotics according to spectrum of action:
I. Narrow-spectrum antibiotics - specific family of bacteria (penicillin G, streptomycin)
II. Broad-spectrum antibiotics - wide range of bacteria, both G+ and G- bacteria (tetracyclines, amfenicols)
III. Slightly-broad spectrum - middle/mean broad antibiotic (semi-synthetic penicillins, aminoglycosides, macrolides)
Special indications - Name anti-staphylococcal antibiotics (6):
Macrolides
Lincomycin
Vancomycin
Penicillinase-resistant penicillins
Cephalosporins of some generations
Rifampicin
Special indications - Name antibiotics against G- bacteria (5):
Aminoglycosides
Polymyxins
Cephalosporins
Tetracyclines
Amphenicols
Special indications - Name antibiotics against yiests and fungi:
Amphotericin B
Nystatin
Grizeofulvin
Candicidin
Natamycin
Trichomycin
Special indications - Name antibiotics for topical application:
Bacitracin
Neomycin
What are requirements for an ideal antibiotic?
- Selective target
- Bactericidal
- Narrow spectrum (does not kill normal flora)
- High therapeutic index
- Few adverse reactions
- Various routes of administration
- Good adsorption
- Good distribution to site of infection
- Emergence of resistance is slow
Name adverse effects of antibiotics in animals:
- allergic reaction
- salivation
- emesis
- diarrhea (disruption of normal flora)
- reduction of vit. B synthesis
- resistency
Name adverse effects of antibiotics in products of animal origin:
- allergic reaction
- depreciation meat injection site
- difficulties in processing the milk fermented products
Name adverse effects of antibiotics in humans:
- occurrence of residues in meat, eggs, milk and edible organs
- development of resistance
Resistance of antibiotics can be either:
Primary - natural
Secondary - obtained
Classification of antibiotics according to chemical structure (11):
- Penicillins
- Cefalosporins
- Tetracyclines
- Amfenicols
- Polypeptides and glycopeptides
- Aminoglycosides
- Macrolides
- Lincosamids
- Ansamycins
- Diterpens
- Different structure
Examples of penicillins:
benzylpenicillin, amoxicilin, ampicilin
Examples of cefalosporins:
cefalexin, ceftiofur
Examples of tetracyclins:
tetracyclin, oxytetracyclin, chlortetracyclin
Example of amfenicols:
florfenicol
Examples of polypeptides and glycopeptides:
Polypeptides: colistin, polymyxin B
Glycopeptides: vancomycin, teikoplanin
Examples of aminoglycosides and aminocyclitols:
Aminoglycosides:
1st gen.: streptomycin, dihydrostreptomycin, neomycin, kanamycin
2nd gen.: gentamicin
3rd gen.: amikacin, netilmicin
4th gen.: izepamycin, daktinomycin
Aminocyclitols:
spectinomycin
Examples of macrolids:
erytromycin, tylosin, tylmikozin, spiramycin
Examples of lincosamides:
linkomycin, clindamycin
Example of ansamycins:
rifaximin
Examples of diterpens:
tiamulin, valnemulin
Examples of antibiotics with different structures:
novobiocin, fusidic acid
Division of beta-lactams:
- Penicillins
- narrow spectrum - benzylpenicillin
- broader spectrum - ampicillin
- beta-lactamase resistant - dicloxacillin, cloxacillin, nafcillin - Cefalosporins
- 1st gen.: cefacetrile, cefapyrin, cefalexin, cefadroxil
- 2nd gen
- 3rd gen.: cefoperazone, ceftiofur, cefovecin
- 4th gen.: cefchinome
Translate into latin:
1. Potassium
2. Procain
3. Benzathin
- Kalicum
- Procanicum
- Benzathinicum
Name methods for testing of effectiveness of antibiotics, advantages and disatvantages:
- Difusion - discs diffusion (qualitative) and E-test (quantitative)
- Dilution - microdilution and macrodilution
Adv.: targeted therapy
Disadv.: time demanding
What is an antibiogram?
Qualitative method for measurement of inhibition zone of antibiotics
What is MIC?
Minimum Inhibitory Concentration
- concentration of drug in blood that can affect inhibition of growth and development of microorganisms