Antibacterials Flashcards
What is the name of the original penicillin formulation?
Benzylpenicillin (or Penicillin G) - still in use today.
How do penicillins and cephalosporins inhibit bacterial cell wall synthesis?
They disrupt peptidoglycan synthesis by inhibiting the enzymes which are responsible for cross-linking the carbohydrate chains.
Penicillins and cephalosporins inhibit enzymes responsible for cross-linking the carbohydrate chains. What are these enzymes known as?
Penicillin-binding proteins (PBPs)
Do glycopeptides act on the same stage of cell wall synthesis as β-lactams?
No - they act on a stage prior to β-lactams.
Can vancomycin be taken orally?
Yes - however only in very special circumstances. It is not absorbed from the GI tract so almost always given parenterally.
Name 3 toxic antibacterials.
Vancomycin, teicoplanin, gentamicin.
Which drugs would commonly be given in the case of penicillin allergy?
Macrolides e.g. erythromycin.
Which is the drug of choice against MRSA?
Linezolid (or daptomycin in serious cases).
Which two drugs are combined to make co-trimoxazole?
Trimethoprim and sulphamethoxazole.
Which drug class can not be used with children?
Fluoroquinolones, due to interference with cartilage formation.
Are fluoroquinolones effective against gram positive or negative bacteria?
Negative.
What is the mechanism of action of trimethoprim and sulphamethoxazole?
Inhibition of nucleic acid synthesis by targeting different steps in purine synthesis.
What is the mechanism of action of aminoglycosides?
Inhibition of protein synthesis.
Name a fluoroquinolone class drug.
Ciprofloxacin.
What advantage does clarithromycin have over erythromycin?
A lower MIC.
