Antibacterials
Drug
Spectrum
MOA
MOR
Pharm
Adverse Effects
Beta-Lactams (Interfere with cell wall synthesis) – all CIDAL
Penicillin G
Ampicillin
Nafcillin
Piperacilin + tazobactam
Cefazolin
(1st generation)
Ceftriaxone
(3rd generation)
Cefipime
(3rd generation)
Imipenem
(Carbapenem)
Gram + cocci/rods
- Susceptible to all b-lactamase,
which works by looking like the
transpeptidase
Gram + cocci/rods
Some gram (-)
Gram + cocci/rods
Broad activity on gram (-)
Activity against orgs
making B-lactamase b/c
of combo w/ inhibitor
Gram + cocci/rods
Some gram (-)
Resembles D-ala so it acts as a
competitive inhibitor and
eliminates transpeptidase
effectiveness.
Gram + and gram (-)
Gram (-) + pseudomonas
Broadest spectrum – last
line b/c very resistant
- b-lactamase resistant!
- PBP resistant
- b-lactamase not inhibited or
overproduced
- Susceptible to Class C and some
Class A gram (-) b-lactamases
- Stable to staphyl penicillinase
- Susceptible to Class A blactamases
- Susceptible to Class A blactamases
- Susceptible to b-lactamases (Class
B) and new KPC enzymes
- Penetration/efflux
All b-lactam antibiotics
are excreted by kidneys
(except nafcillin), so
dosing must be altered
in renal failure
Hypersensitivity
Type I: urticarial and
anaphylaxis
Type II: hemolytic anemia
Type III: immune
glomerulonephritis, drug
fever
Type IV: contact dermatitis,
maculopapular eruptions
Type V: drug fever,
maculopapular eruptions,
dermatitis
Glycoproteins (Interfere with cell wall synthesis)
Gram + cocci
Vancomycin
CIDAL
Binds to D-ala, D-ala in
peptidoglycan stem peptide
and inhibits both
transpeptidation and
transglycosylation.
- D-ala, D-ala changed to new stem
peptide like D-ala D-lactate
- Acquired resistance in enterococci
+ s. aureus isolates (develop lower
susceptibility to vancomycin)
IV only, long serum
half-life, excreted only
by kidney (no
metabolism), higher
half-life in renal insuff.
- “red man syndrome” due to
histamine release
- renal and ototoxicity cited
- GI colonization w/ VRE
promoted w/ oral route.
Binds 50S of ribosome and
blocks protein synthesis
(prevents elongation).
- Efflux (strep esp.)
- Methylation of ribosomal binding
site
- Mutation of 23S ribosomal binding
site
Metabolized/excreted
by liver
- Block hepatic CYP  fatal
GI SE due to higher GI motility
- Bile status in liver due to
some oral prep. of
erythromycin (cholestasis)
- Cardiac arrhythmias
Binds 50S of ribosome and
blocks protein synthesis
(prevents elongation).
- Methylation of ribosomal binding
site
- Active efflux
Interfere with protein synthesis
Gram +
Intracellular bacteria
Macrolides
(azithromycin/
erythromycin)
STATIC
Lincosamides
(clindamycin)
Gram +
Obligate anaerobes
Intracellular bacteria
STATIC
C diff-associated colitis
Aminoglycosides
(gentamicin)
Tetracyclines
(doxycycline)
Gram (-) bacilli
Some gram +
Synergy w/ cell wall
inhibitor such as PCN or
vancomycin
CIDAL
Broad – many gram + and
gram (-)
Some obligate anaerobes
Some intracellular bact.
Bind to 30S of ribosome and
blocks formation of initiation
complex and mRNA reading.
- Modification of OH groups on
rings (acetyl-, adenyl-, phosphorylation)
- Active efflux
Combined with PCN to
treat enterococcus:
(PCN-disrupts cell wall,
aminoglycosides get in
and rapidly kill cells)
- Nephrotoxicity
- Ototoxicity – hearing loss
Binds to 30S ribosomal
subunit – blocks association of
amino-acyl tRNA
- Efflux (tetracycline specific)
- Ribosomal protection – blocks
binding of drug to ribosomal target
- Phototoxicity
- Contraindicated in children
– discoloration of teeth,
inhibit bone maturation.
SMX alone blocks
dihydropteroate synthetase
(which produces folic acid) by
comp. inhibition.
SMX + Trimethoprim inhibits
dihydrofolate reductase
resulting is sequential
blockage “synergy.”
- Other target enzymes that resist
drug inhibition but active in folic
acid synthesis (DHPS + DHFR)
- Trimethoprim most active in SMXTMP combo so resistance is limited
to trimethoprim.
- Hypersensitivity, skin reason
(erythema multiforme),
hepatitis, aspetic meningitis,
high rates of rash.
Binds to topo II (DNA gyrase)
and topo IV, preventing
binding to gyrase/DNA
complex – prevents DNA
replication/repair.
- Mutations in target – gyrase/topo
- Active efflux
- Limiting for E. coli UTI
- Contraindicated in
pregnancy and for children
- Achilles tendon rupture
STATIC
Antimetabolite
Sulfonamide (SMX)
Trimethoprim
(Diaminopyrimidines)
Gram +
Gram (-)
Unusual
Disruption of Nucleic Acid Synthesis/Function
Fluoroquinolones
(ciprofloxacin,
levofloxacin)
Gram (-)
Intracellular bacteria
s. pneumo (gram +)
shigella + salmonella
CIDAL
Membrane Perturbation
Polymixins
Last resort for
multiresistant gram (-)
Cationic charge on gram-neg
outer membrane
Daptomycin
Gram +
CIDAL for s. aureus
Gram + inner membrane
charge change
nephrotoxicity