Antibiotics - Hanson Flashcards
Pen G/V
Natural
Acid labile - IV only
Narrow spec
Gram + (esp strep, staph doesn’t respond due to PCNase)
avoid in staph
PCNase Resistant (Nafcillin, oxicillin)
MRSA
TX for staph - not good in strep
Aminopenicillins (amp and amox)
Spec - some gram + (good for strep, not staph)
Good for UTI (gram -)
Expanded Spec (ticarcillin, pipercillin)
Good for gram - (not gram +)
Very $$$
Reserved for hospital use
Good against pseudomonas and gut gram +
Bacteria characteristics
Gram + don’t have capsule – easier access to cell wall
Gram - have capsule which prevents access to PCN binding proteins
PCN Spectrum
Natural (V/K) - Strep
PNCase (Nafcillin, oxicillin) - Staph
Amionpenicillin (amp and amox) - strep
Expanded (ticarcillin, pipercillin) - pseudomonas and gram -
PCN Resistance
Failure to bind to PCN binding proteins
-due to outer capsule on gram -
Mutated porins
PCN PK
Does not cross BBB except in inflammation – which may increase risk for seizures
Renal excretion - probenacid may be added to TX to prevent renal excretion and increase PCN action in urinary tract
PCN SE
Hypersensitivity - anaphylaxis
-allergy to beta-lactam potion
GI
Seizures
PCN DDI
Aminoglycosides - the two MOA go against each other except broad spec ticacillin
Low doses EE OC - alters gut bacteria that may decrase OC efficacy
1st Gen Cephalosporin
Cefazolin, cephalexin
More gram -, some good gram +
Good substitute for PCN
Not good against MRSA
2nd Gen Cephalosporin
Cefuroxime, cefaclor
Good against gram - (not as good as 3rd gen)
Not really used
3rd Gen Cephalosporin
Ceftizoxine, ceftriaxone, cefixime
Good against gram -
Resistant to beta lactamase
Not good against staph
4th Gen Cephalosporin
Cefepime
Good against gram -
Resistant to beta lactamase
Cephalosporins
MOA - beta lactam and dihydrothiazine ring
Able to cross capsule better than PCN
No BBB
Hypersensitivity - less than with PCN
