Y4 - Prudent Antimicrobial Prescribing Flashcards
Which antibiotics inhibit cell wall synthesis?
Penicillins Cephalosporins Carbapenems Daptomycin Glycopeptides
What antibiotic inhibits DNA synthesis?
Fluoroquinolones
What antibiotic inhibits RNA synthesis?
Rifampicin
What antibiotics inhibit protein synthesis?
Macrolides Chloramphenicol Tetracycline Aminoglycosides Oxazolidonones
What antibiotics inhibit folic acid synthesis?
Sulfonamides
Trimethoprim
True or false:
Bactericidals work faster than bacteriostatics
True
Which antibiotics are bactericidal?
Beta-lactams Glycopeptides Fluoroquinolones Cephalopsorins Daptomycin Aminoglycosides
Which drugs are bacteriostatic?
Tetracyclines Clindamycin Sulfonamides Chloramphenicol Linezolid
Which drugs are intermediate (can be bactericidal or bacteriostatic)?
Macrolides
What antibiotics are beta-lactams?
Penicillins, carbapenems, cephalosporins
What is the structure of beta-lactams and how do they work?
Contain a beta-lactam ring which inhibits formation of peptidoglycan cross links in the bacterial cell wall
What must you do before using carbapenems?
Seek microbiology advise
Give examples of antibiotics which are glycopeptides
Vancomycin and teicoplanin
Bactericidals should always be used for what group of patients?
Immunocompromised patients
What are the mechanisms of bacterial resistance to antibiotics?
- Bacteria acquire genes encoding enzymes to inactivate antibiotics, e.g. B-lactamases
- Bacteria finds alternative metabolic pathway, e.g. trimethoprim
- Alteration of the target site so antibiotic is no longer able to bind
- Decreased permeability via porin channels in the cell wall
- Antibiotic is removed from the bacteria via an efflux pump, e.g. tetracyclines
What is the difference between penicillin V (phenoxymethylpenicillin) and penicillin G (benzylpenicillin)?
Penicillin G is IV only
Penicillin V is oral only
What is the coverage with penicillin V/benzylpenicillin?
Streptococci
Enterococci (faecalis & faecium)
Moderate coverage of anaerobes
What are coliforms?
Gut bacteria, e.g. E. coli
Give examples of atypical bacteria
Legionella
Chlamydia
Mycoplasma pneumoniae
Myobacterium tuberculosis
Why are bacteria classed as atypical?
They don’t gram stain
What is coagulase negative staph?
Any staph that is not staph aureus
What is the coverage of flucloxacillin?
Staph, strep
Best for staph aureus
What is the coverage of amoxicillin?
Strep
Enterococcus faecalis
Moderate anaerobe, coliform and respiratory (e.g. H. influenzae, Moraxella catarrhalis) cover
What is the coverage of co-amoxiclav?
Staph Strep Enterococcus faecalis Anaerobes Coliforms Respiratory
What is co-amoxiclav?
Amoxicillin + clavulanic acid (Beta-lactamase inhibitor)
Helps overcome beta-lactam resistance
What are the broad spectrum penicillins?
Piperacillin/tazobactam
Cover staph, strep, enterococcus faecalis, anaerobes, coliforms, respiratory pathogens and pseudomonas aeruginosa
What are the two carbapenems?
Ertapenem and meropenem
What is the coverage of the carbapenems?
Ertapenem and meropenem cover staph, strep, Ef, anaerobes, coliforms, respiratory, ESBL
Meropenem also covers pseudomonas aeruginosa
What are the cephalosporins?
Cefalaxine (1st gen) Cefuroxime (2nd gen) Cefotaxime & ceftriaxone (3rd gen) Ceftaroline (5th gen) Ceftazidime/avibactam
What is the coverage of 1st to 5th generation cephalosporins and what trend does coverage follow as the generations become later?
All cover staph, strep and coliforms,
After 2nd generation, all moderately cover anaerobes and cover respiratory well
3rd and 5th generation moderately cover ESBL
5th generation covers MRSA
What are the tetracyclines?
Tetracycline
Doxycycline
What is the coverage of doxycycline?
MRSA Staph Respiratory Atypicals Moderately covers ESBL, strep, anaerobes
What is the coverage of trimethoprim?
Moderately covers MRSA, staph, strep, Ef, coliforms, respiratory