Antimicrobials I Flashcards
Agents that inhibit bacterial cell wall synthesis (classes)
penicillins, cephalosporins, vancomycin, carbapenems, monobactams
Angetns that affect protein synthesis (classes)
macrolides/lincosamindes, tetracyclines, aminoglycosides, linezolids (chlormphenicol, streptogramins, oxazolidinones)
Agents that affect bacteria nucleic acid metabolism
quinolones (and rifamycins)
Agents which block folate metabolism
trimethoprim and sulfonamide
Miscellaneous agents
daptomycin and metroniazole
Mechanism of resistance to penicillins
efflux pumps, changes in the permeability channels, beta lactamase, or mutations of the penicillin binding proteins (esp. gram positives)
major adverse effect of penicillins
allergy: rash to anaphylaxis
may cause lower the seizure threshold
may have bone marrow suppression effects, esp. with WBCs (ESPECIALLY nafcillin)
Penicillin: coverage, sides, administration
strep, syphillis, gram pos cocci, some enterococci. PO for penK, IV for Pen G, IM for syphilis
Nafcillin/oxacillin: coverage, sides
covers MSSA and strep. not enterococci or gram negativivs. Nafcillinc can cause profound neutropenia. oxacillin can cause hepatic stasis. both can cause AIN. bulky side chains resist staph beta lactamases
ampicillin/amoxicillin: coverage, administration
good for strep A and B, MSSA, gram neg rods like E coli. IV or PO.
Piperacillin/ticarcillin. uses, andmin, CNS
good for pseudomonas (but requires a higher dose: 4.5 q 6 hrs), staph, gram negatives, anaerobes. Taz is a beta lactimase inhibitor. IV only and doesn’t reach CNS.
unasyn
kil staph, strep, and enterococcus. does not kill pseudomonas. aka amp and sulbactam. IV only.
Augmentin
amoxicillin + clauvulante. good for staph, strep, enterococcus. doesn’t kill pseudomonas. good for recent dental infections, those who have had ampicillin recently, non-MRSA skin infections. ORALLY available.
First generation cephalosporins
cefazolin and cephalexin.
cefazolin
1st generation cephalosporin used for cellulitis and surgical procedures. give IV. coveers stap, strep, some gram neg rods like E coli and klebsiella (no enteroccoccus, anaerobes, pseudomonas)
cephalexin
1st gen cephalosporin. covers staph, strep, some gram neg rods (E coli, klebsiella). doesn’t cover enterococcus. this is oral. used for cellulitis, surgical prophylaxis, and strep in kids.
What should I know about 2nd generation cephalosporins?
rarely used. two kinds- respiratory group (cefuroxime) (covers s pneumon, h flu, m catt, strep), and anaerobic group cefotetan (covers GNE, anaerobes, strep). cephotetan has a disulfram effect.
Ceftriaxone: class, admin, CNS? use
3rd gen cephalosporin given Q24 hrs. has CNS penetration:
Ceftriaxone: use
first choice for meningitis caused by pneumonococcus and meningococcus. and in hospital pts with community acquired pneumonia.
covers S pneumo, enteric gram negatives, and meningococcus
Ceftriaxone: side effects
biliary sludge- but no worries about renal pts
Cefotaxime: class, use, admin
IV, 3rd gen cephalosporin, treats S pneumo, enteric gram negatives, meningococcus. used for meningitis caused by pneumococcus and meningococcus and in hospital pts with CAP. covers S pneumo, enteric gram negatives, and meningococcus
What 3 generation cephalosporin covers pseudomonas?
ceftazidme
use of ceftazidme
gram negative CNS infections, including pseudomonas. not as good for gram positive coverage or enterococcus
