Flashcards in Antibiotics Deck (23)
Name B-lactam antibiotics
Pencillins - penicillin, flucloxacillin, amoxicillin, piperacillin/tazobactam
Cephalosporins - ceftriaxone, ceftazidime, carbepenems
How do B-lactam antibiotics work?
Stop crosslinking of peptidoglycan and cause autolysins to degrade cell wall (bactericidal)
What is the coverage of B-lactams?
Some gram -ve
How do glycopeptides work?
Enter cell and bind to PG precursor molcule so they cannot be crosslinked - weak cell wall results in osmolysis (bactericidal)
What is the coverage of glycopeptides?
Gram positive only
How do macrolides work?
Pass through cell membrane and act on ribosomes to prevent peptide bonds being formed (bacteristatic)
How do aminoglycosides work?
Bind to ribosome causing misreading of mRNA codon and insertion of wrong amino acid onto protein (bactericidal)
What are aminoglycosides effective against?
Gram negative aerobic organisms
What are macrolides used for?
Infections where bacteria 'hide' from immune system (legionella)
Bacteria without a proper cell wall (mycoplasma, chlamydia)
How do tetracyclines work?
Inhibit protein synthesis by binding to ribosomes (bacteristatic)
What are tetracyclines used for?
Bacteria without a proper cell wall
Infections in penicillin-allergic patients
How does metronidazole work?
Strand breakage of DNA (bactericidal)
What does metronidazole cover?
True anaerobes - clostridium, bacteriodes
How does trimethoprim work?
Inhibits bacterial folic acid synthesis
What does trimethoprim cover?
Gram negatives and some gram positive
How do fluoroquinolones work?
Interact with topoisomerases responsible for DNA coiling (bactericidal)
What is the coverage of fluoroquinolones?