exam 4 Flashcards
Beta lactams
subgroups
MOA
Adverse effects
Drug interactions
Fun fact
PD
Penicillins, Cephalosporins, Carbapenems, Monobactams
MOA - Bind to penicillin binding proteins in the cell wall
of susceptible bacteria. This ultimately causes interruption in cell wall synthesis, resulting in bacterial cell lysis and death.
Adverse effects:
◦ Hypersensitivity reactions ◦ GI disturbances (oral) ◦ CNS toxicity (particularly in renal dysfunction) ◦ Nephrotoxicity
Drug Interactions
◦ Probenicid
fun fact - Almost all beta lactams require dose adjustment in renal dysfunction
Pharmacodynamics of this class important to
understand
◦ Efficacy measured as time above MIC of the bacteria
◦ Newer dosing strategies utilize prolonged infusions (3-4
hours) Commonly done with antipseudomonal agents
what are the penicillin groups
Natural Penicillins Aminopenicillins Penicillinase-Resistant Penicillins Extended-spectrum Penicillins Beta-lactamase Inhibitors
Natural penicillins
subgroups
spectrum
clinical uses
subgroups - Penicillin VK (Veetids), Penicillin G sodium or potassium (Pfizerpen), Penicillin G benzathine (Bicillin-LA), Penicillin G procaine/benzathine (Bicillin-CR)
Spectrum -
◦ Streptococcus sp.
◦ Mouth anaerobes
◦ T. pallidum
Clincal uses -
◦ Streptococcal pharyngitis
◦ Necrotizing fasciitis (group A strep – in combo with clindamycin)
◦ Syphillis (all stages)
Jarisch-Herxheimer reaction common
Penicilinase-resistant penicillins
drugs in this class (fun fact about two)
spectrum
adverse events
common clinical uses
drugs are: Nafcillin (Nafcil), Oxacillin (Bactocil) (Undergo biliary excretion – only penicillins that do not require adjustment in renal dysfunction), Dicloxacillin (Dynapen)
Spectrum:
◦ MSSA – often considered drug of choice
◦ Streptococcus sp
Adverse events:
◦ Acute interstitial nephritis
Nafcillin>oxacillin
Common clinical uses:
◦ Cellulitis
◦ Bacteremia/endocarditis
◦ Osteomyelitis
Aminopenicillins
drugs in this
spectrum (DOC?)
Drugs in this - amoxicillin, ampicillin
Spectrum - A SLEEP H
G+ - anaerobes, streptococcus sp, listeria sp, enterococcus sp DOC
G- - E coli, Proteus sp, H influenza
Extended-spectrum penicillins
drug (whats special)
Spectrum (+/-)
piperacillin (pipracil) - no longer on market
spectrum:
+
Streptococcus
Enterococcus
-
aminopenicillin
enterobacterales
P. aeruginosa
acinetobacter
Beta lactimase inhibitors
MOA
currently available combinations
spectrum
MOA: prevents hydrolytic action on penicillin and also binds directly to penicillin-binding proteins to increase antibacterial activity
Currently available combinations:
◦ Amoxicillin/clavulanic acid (Augmentin)
◦ Ampicillin/sulbactam (Unasyn) *also covers Acinetobacter sp.
◦ Piperacillin/tazobactam (Zosyn)
Spectrum:
◦ Increased gram negative coverage
◦ Increased anaerobic coverage
First generation cephalosporins
Drugs in this class
spectrum
cefazolin
cephalexin
cefadroxil
◦ Gram positive
Streptococcus sp. MSSA
◦ Gram negative
E. coli Klebsiella spp. Proteu
Second generation cephalosporins
Names
which indicate anaerobic activity and which indicate MTT
spectrum
Cefotetan (anaerobic activity and MTT)
cefoxitin (anaerobic activity)
cefprozil
cefaclor (exception to word rules)
cefurozime (exception to rule)
Spectrum is increased gram neg coverage and H influenza
Third generation cephalosporins
Which drugs in this class
spectrum
cefdinir
cefpodoxime
cefixime
ceftazidime
cefotazime
ALL DRUGS THAT END IN “ME IR ONE” except for cefurozime!
Spectrum
most retain relatively decent gram pos activity except ceftazidime.
all cause increased gram negative activity such as enterobacterales (ceftazidime only agent w activity against P aerugonisa)
only agent with activity against P aerugonisa
ceftazidime
what third gen cephalosporin has antipseudomonal activity
ceftazidime
what second gen cephalosporin interacts with warfarin to cause increased bleeding
cefotetan
Fourth generation cephalosporin
drugs in this class
spectrum
drugs: cefepime
spectrum
good gram positive activity (strep/MSSA)
excellent gram neg
NO anaerobic activity
what is penicilinase-resistant pencillin used for a drug of choice
MSSA
