EXAM 2 Penicillins Flashcards
B-lactams are primarily unchanged in the kidneys except for..
nafcillin, oxacillin, ceftriaxone, cefoperazone
B-lactams have cross allergenicity except for
aztreonam
can be used in penicillin allergy
penicillin MOA
Bactericidal
interfere w/ cell wall synthesis by binding PBPs
Penicillin mechanism of resistance
production of b-lactamase enzymes
Alteration in structure of PBPs
alteration of outer membrane porin
production of b-lactamase enzymes
produced by
gram (+): penicillin-resistant staph aureus
gram (-):
gram(-) anaerobes: bacteroides
alteration in structure of PBPs
leads to decrease binding affinity
MRSA, PRSP
alteration of outer membrane porin proteins
lead to decreased penetration
natural penicillins
Aqueous penicillin G
benzthine penicillin G
procaine penicllin G
Phenoxymethyl penicillin (pen VK)
natural penicillins spectrum
do not target any blue bugs
penicillinase resistant penicillins
Nafcillin and dicloxacillin
nafcillin spectrum
MSSA
aminopenicillins
ampicillin and amoxicillin
ampicillin spectrum
no blue bugs
carboxypenicillins
ticarcillin
ticarcillin spectrum
pseudomonas aeruginosa
ureidopenicillins
Piperacillin
piperacillin spectrum
pseudomonas aeruginosa
penicillin of choice
b-lactamase-inhibitor combos
parental: ampicillin-sulbactam(unasyn), piperacillin-tazobactam (zosyn)
oral: amoxicillin-clavulanate (augmentin)
Ampicillin/sulbactam (unasyn) and Amoxicillin/clavulanate (augmentin) spectrum
MSSA
Piperacillin/tazobactam (zosyn) spectrum
MSSA
Psuedomonas
BDA (bacteroides)
Which penicillin is consdidred a potential drug of choice for infections due to MSSA?
A. Pen G
B. Ticarcillin
C. Ampicillin
D. Nafcillin
E. Piperacillin
D. Nafcillin
Which penicillin is considered drug of choice for infections due to Pseudomonas aeruginosa?
A. Pen G
B. Ampicillin/sulbactam
C. Amoxicillin
D. Nafcillin
E. Piperacillin
E. Piperacillin
Penicillin distribution
widely distributed into tissues and fluids
Adequate CSF concentrations of pens (but NOT b-lactamase inhbitors) are ONLY achieved in the presence of inflamed meninges w/ high-dose parenteral administration
penicillins elimination
most are eliminated unchanged in the kidneys –> dosage adjustment required in renal insufficiency
NAFCILLIN and OXACILLIN are eliminated primarily by the liver –> no dose adjustments in renal insuffiiciency
sodium load
must be used in cuation in patients with CHF or renal insufficiency
Ticarcillin - 5.2mEq
Nafcillin - 2.9mEq
Sodium PenG - 2.0mEq
Piperacillin - 1.85mEq
Which one of the following is not a general characteristic of b-lactam antibiotics?
A. inhibition of cell wall synthesis
B. long elimination half-lives
C. Primarily eliminated by the kidney
D. Bactericidal
E. Degradation by b-lactamase enzymes
B. long elimination half-lives
penicillin adverse effects
hypersensitivity
neurologic - seizures
hematologoic - neutropenia, thrombocytopenia
Interstitial nephritis (especially in nafcillin)
T/F: A patient who developed a rash to penicillin can safely take augmentin
FALSE
