Bactericidal drugs kill bacteria.
Which class of drugs slows bacterial growth?
Bactericidal
Bacteriostatic
When a bacteriostatic drug is added to an in vitro colony of bacteria, what will happen to the the number of bacteria?
Increase
Decrease
Stay the same
When a bactericidal drug is added to an in vitro colony of bacteria, what will happen to the the number of bacteria?
When a bacteriostatic drug is removed from an in vitro colony of bacteria, what will happen to the the number of bacteria?
When a bactericidal drug is removed from an in vitro colony of bacteria, what will happen to the the number of bacteria?
Are the actions of sulphonamides bactericidal or bacteriostatic?
Concentration dependent
Is the action of trimethaprim bactericidal or bacteriostatic?
Are the actions of tetracyclines bactericidal or bacteriostatic?
Is the action of chloramphenicol bactericidal or bacteriostatic?
Is the action of linomycin bactericidal or bacteriostatic?
Is the action of erythromycin (macrolides) bactericidal or bacteriostatic?
Are the actions of penicillins bactericidal or bacteriostatic?
Are the actions of cephalosporins bactericidal or bacteriostatic?
Are the actions of fluoroquinolones bactericidal or bacteriostatic?
Are the actions of aminoglycosides bactericidal or bacteriostatic?
Is the action of metronidazole bactericidal or bacteriostatic?
A potentiated sulphonamide refers to which of the following combinations of antibacterial agents?
Sulphonamide and Erythromycin
Sulphonamide and Fluoroquinolone
Sulphonamide and Trimethoprim
Sulphonamide and Chloramphenicol
Sulphonamide and Cephalosporin
What is the main aim for optimum efficacy of a time dependent drug?
Plasma levels should be above minimum inhibitory concentration (MIC) for as long as possible in each 24 hour period
Plasma levels should be as high as possible for as long as possible
The dosage is irrelevant, but the drug must be in the system for as long as possible
Which of the following drugs is time dependent?
Aminoglycoside
Penicillin
Fluoroquinolones
Metronidazole
Cephalosporin
Fluoroquinolone
Which of the following drugs are concentration dependent?
Metronidasole
Where are NAMA and NAG synthesised?
Cytoplasm
Membrane
Extra-membrane
How many peptides are initially attached to NAMA?
3
4
5
6
What is the most important feature for the activity of a penicillin/cephalosporin?
Ring of 2 carbons and 2 nitrogens
Ring of 3 carbons and 1 nitrogen
Ring of 5 carbons
Ring of 5 carbons and 1 nitrogen
Ring of 4 carbons and 2 nitrogens
What determines the antibacterial activity of β-lactams?
R side chain
Ability to bind to peptidyl transferase
Ability to bind to transpeptidases
Drug size
Ability to bind to gamma-glutamyl transpeptidase
The ability for penicillin to access transpeptidase is limited in gram +ve bacteria.
Clavulanic acid has an antibacterial effect when administered alone.
Which of the following drugs would be best paired with clavulanic acid?
Mecillinam
Cloxacillin
Benzylpenicillin
Methicillin
Amoxicillin
Benzylpenicillin has good acid stability.
Which of the following drugs are susceptible to β-lactamase activity?
Penicillin V
Ampicillin
Carbenicillin
Which of the following drugs are not susceptible to β-lactamase activity?
Which of the following drugs are most effective against Gram +ve cocci?
Which of the following drugs is most active against Gram -ve bacteria?
Which of the following drugs is efficacious against pseudomonas?
Which generations of cephalosporins are unstable in acid?
1st generation
2nd generation
3rd generation
4th generation
Which generation of cephalosporin has the least β-lactamase stability?
Which generations of cephalosporin are least susceptible to β-lactamase activity?
Which of the following drugs is most efficacious against gram +ve bacteria?
Cephalexin
Cefuroxime
Cefovecin
Cefquinome
Which of the following drugs is most efficacious against gram -ve bacteria?
Cephradine
Penicillins and cephalosporins are eliminated by the liver.
Penicillins do not cross the BBB, despite being widely distributed.
Some cephalosporins cross the BBB.
Aminoglycosides induce a long lasting mutation in bacteria, so are risky to use given that resistance may easily occur.
What type of bacteria are aminoglycosides more efficacious against?
Gram -ve anaerobic bacteria
Gram -ve aerobic bacteria
Gram +ve anaerobic bacteria
Gram +ve aerobic bacteria
Aminoglycosides are typically bactericidal.
Aminoglycosides have poor oral bioavailability.
How are aminoglycosides eliminated from the body?
Liver metabolism
Renal excretion
Excreted in bile
Metabolism in muscles
How do macrocodes inhibit bacteria protein synthesis?
Bind to ‘A’ site, prevent initiation
Bind to ‘P’ site, prevent translocation
Bind to ‘E’ site, prevent translocation
Bind to ‘A’ site, prevent termination
What type of bacteria are macrocodes more efficacious against?
Gram -ve
Gram +ve
Macrocodes have poor oral bioavailability.
How are macrolides eliminated from he body?
Metabolised by liver
At doses normally used in veterinary practice, erythromycin is bactericidal.
How do lincosamides inhibit bacteria protein synthesis?
Bind to 'A' site, prevent initiation
Bind to 'P' site, prevent elongation
Bind to 'E' site, prevent elongation
Bind to 'E' site, prevent termination
How do tetracyclines inhibit bacterial protein synthesis?
Which class of bacteria are tetracyclines most effective against?
Gram +ve aerobes
Gram +ve anaerobes
Gram -ve aerobes
Gram -ve anaerobes
Wide spectrum against aerobic and anaerobic Gram +ve and –ve bacteria
Tetracyclines have a bacteriostatic effect.
How are tetracyclines eliminated from the body?
Metabolism by the liver
Metabolism by muscles
Tetracyclines inhibit mammalian protein synthesis. Why are the side effects not more severe than those observed if this is the case?
The drug is delivered directly to the site of action, minimising the systematic effect
The concentration is not high enough to affect mammalian cells
Mammalian cells do not efficiently transport tetracyclines across cell membrane
Tetracyclines on affect cells with a cell wall
How does chloramphenicol inhibit bacterial protein synthesis?
Binds to 'A' site, inhibits initiation
Binds to 'P' site, inhibits elongation
Inhibits peptide bond formation
Binds to 'E' site, inhibits termination
Chloramphenicol is banned in food-producing animals
Chloramphenicol had poor oral bioavailability.
Chloramphenicol can cross the BBB.
Chloramphenicol has a bacteriocidal effect.
How is chloramphenicol eliminated from the body?
Metabolised in muscles
In which class of bacteria is chloramphenicol most efficacious?
Gram positive aerobes
Gram negative aerobes
Obligate anaerobes
Penicillinase producing - Staphylococcus
Which of the following drugs affect folate synthesis?
Cyclosporins
Chloramphenicol
Sulphonamides
Tetracycline
Trimethoprim
Which class of bacteria are sulphonamides most efficacious against?
Gram - aerobes
Wide spectrum against Gram +ve and –ve bacteria
Sulphonamides have poor oral bioavailability.
Sulphonamides can cross the BBB.
How are sulphonamides excreted from the body?
Metabolised by the liver
Metabolised by muscles
Sulphonamides have a bacteriostatic effect.
How does trimethoprim affect bacterial folate synthesis?
Inhibits uptake of p-aminobenzoic acid (PABA)
Inhibits dihydropteroate synthetase (DHPS)
Inhibits dihydropteroate reductase (DHPR)
Inhibits dihydrofolate synthetase (DHFS)
Inhibits dihydrofolate reductase (DHFR)
How are fluoroquinolones eliminated form the body?
Fluoroquinolones have poor oral bioavailability
Fluoroquinolones have a bactericidal effect.
Which class of bacteria is metronidazole most efficacious against?
Penicillinase producing Staphylococcus
Metronidazole has good oral bioavailability
Metronidazole can cross the BBB.
How is metronidazole eliminated from the body?
Biliary excretion