Pharm - Monobactams/Carbapenems/B lactamase inhibitors Flashcards
true or false
monobactams are beta lactams
true
differentiate between the spectrum of beta lactams vs monobactams
monobactams have a much narrower spectrum and are really reserved for pseudomonas infection
active against AEROBIC GRAM NEGATIVE RODS (pseudomonas)
monobactams are INACTIVE AGAINST:
gram positive bacteria and anaerobic bacteria
explain what monobactams are/are not resistant to
are resistant to many b lactamases
not resistant to chromosomal encoded beta lactamases (AmpC and extended spectrum)
name a monobactam
aztreonam
how is aztrenoam administered
monobactam
IV/IM
distribution aztreonam
good - distributes to CSF
true or false
there are no MAJOR hypersensitivities for aztreonam
true
however, there is occassional elevation of aminotransferases, an indicator of hepatotoxicity
MOA of monobactams
same as beta lactams, just binds to PBP-3 and PBP1A
name 4 carbapenems
doripenem
etrapenem
imipenem
meropenem
importans consideration when administering imipenem
by itself, it will be inactivated by the kidneys (dehydropeptidases) in the renal tubules
THEREFORE, we always give it with cilastatin
spectrum imipenem
broad - gram pos, neg, anaerobes
DOES NOT cover MRSA, C DIFF, ENTEROCCI
imipenem is resistant to beta lactamases but not…..
carbapenamases or metallo-B lactamases, C diff, or MRSA
how is imipenem excreted
renally - need to lower dose
clinical uses carbapenems
reserved antibiotics
for bacteria that are resistant to other drugs (like pseudomonas), mixed aerobe and anaerobic infections, enterobacter infections
AE of carbapenems that is common to all b lactams
seizures in impaired kidney function and you give high dose
is there any penicillin cross-sensitivity in carbapenems
low but possible
which carbapenem has a longer half life? it is thus best for which infections?
etrapenem - good for abdominal infections
true or false
both carbapenems and monobactams are bacteristatic
FALSE - both bactericidal
have basically same MOA - present cell well synthesis by binding and inhibiting transpeptidases
true or false
beta lactamase inhibitors are NEVER used as single agents
true always combined with penicillins or cephalosporins
they do not kill bacteria - just extend spectrum
name 4 beta lactamase inhibitors
clavulanic acid
sulbactam
tazobactam
avibactam (not chemically a beta lactam, but still beta lactamase inhibitor)
chemically, the other 3 are beta lactams
MOA beta lactamase inhibitors
potent IRREVERSIBLE inhibitors of bacterial beta lactamases (NOT ALL OF THEM - NOT AGAINST CHROMOSOMALLY ENCODED ENTEROBACTER, CITROBACTER, OR PSEUDOMODAS)
true or false
beta lactamase inhibitors are reversible inhibitors of beta lactamases
FALSE - irreversible
name 6 penicillins/cephalosporins that come with B lactamase inhibitor
amoxicillin (clav)
ampicillin (sulbactam)
pipercillin (tazobactam)
ticarcillin (clav)
ceftazidime (avibactam)
ceftolozane (5th gen) (tazobactam)
what is the spectrum of the beta lactamase inhibitors
do NOT have their own spectrum - it’s the same as that of the beta lactam used with it
indications for using beta lactamase in combo with beta lactams
empiric therapy - when need wide range of treatment for mixed aerobe and anaerobe
(like intra-abdominal infection)
beta lactamase inhibitors extend the effect of penicillin to ___________ bacteria
bacteria that produce beta lactamase
EXTEND THE SPECTRUM
What are “class A beta lactamases”
inhibit plasmid encoded beta lactamases
beta lactamase inhibitors resemble what?
beta lactams
beta lactamase inhibitors protect…..
penicillins and cephalosporins
