Antibiotics Flashcards
penicillin MOA
Cell Wall Synthesis Inhibitor
penicillin adverse effects
nephrotoxicity, allergic interstitial nephritis, seizures (toxic levels due to renal dysfunction), diarrhea, C. difficile infection (with broader spectrum)
penicillin ___ killing, half life
Time-dependent killing; most effective against microorganisms rapidly growing + dividing
* Very short half-life <2 hrs; dosed multiple times/day
penicillin for special population
safe for infants and pregnancy
dose adjustment for renal dysfunction
penicillin has sensitivity to
cephalosporins
amoxicillin is __ spectrum
broad spectrum
cephalosporin MOA
Cell Wall Synthesis Inhibiton
adverse effects of cephalosporin
GI intolerance, seizures (high doses), interstitial nephritis, rare
blood dyscrasias,
***C. difficile infection
cephalosporin is ___ killing
Time-dependent killing; most effective against microorganisms rapidly growing + dividing
- Renal elimination for all except ceftriaxone (liver) – adjust dose prn
CSF penetration of cephalosporin
1st + 2nd Gen: low CSF penetration – do not use for bacterial meningitis
special population for cephalosporin
Safe for use in infants/children (avoid ceftriaxone in neonates -> bilirubin displacement and kernicterus )
Crosses placenta + present in breastmilk Generally safe in pregnancy/breastfeeding
Adjust dose with renal dysfunction for older adults
CARBAPENEMS MOA
Cell Wall Synthesis Inhibitor
adverse effects of carbapenems
confusion, delirium, seizure, diarrhea, C. difficile infection anemia, ↑LFT’s
carbapenems ____ killing
_____ CSF
Time-dependent killing
* Post-antibiotic effect
* Penetrates CSF
Drug interactions of carbapenems
valproic acid (reduced effect -> seizures)
monitoring for carbapenems
renal/liver/hematologic function periodically
penicillin monitoring for
renal function with renal disease
cephalosporin monitoring for
c. diff symptoms
monobactams MOA
Cell Wall Synthesis Inhibitor
adverse effects of monobactams
thrombophlebitis at injection site, neutropenia + ↑lft’s in peds, C. difficile infection
monobactams are___ killing
____ CSF
Time-dependent killing
* Penetrates CSF
beta lactam antibiotics metabolism and elimination
except
- Minimal hepatic metabolism
- Renal elimination (adjust dose prn)
except ceftriaxone (liver) – adjust dose prn
monobactams special population
Not recommended in pediatric CNS infections due to seizure risk
Crosses placenta + present in breastmilk Use only if safer alternative not available.
Adjust dose with renal dysfunction for older adults
__ generations of cephalosporin
There are 5 generations and as they proceed from the 1st to the 5th generation, there is more gram negative and anaerobic coverage, less resistance to beta lactamases and more CSF penetration.
vancomycine MOA
Cell Wall Synthesis Inhibitor
vancomycine is reserved for ___
Reserve for Gram (+) infections where B-lactams cannot be used
adverse effects of vancomycin
renal toxicity,
ototoxicity (tinnitus, hearing loss, vertigo/dizziness),
neurotoxicity, hypersensitivity/anaphylaxis,
C. difficile (IV use),
thrombocytopenia, neutropenia, pancytopenia, thrombophlebitis, infusion reaction with rapid administration (red man syndrome)
pharmacokinetics of vancomycin
____ killing
metabolism and elimination
Time-dependent killing
* Post-antibiotic effect
* No B-lactam ring
* Poor GI absorption; minimal hepatic metabolism
* Renal elimination (adjust dose prn)
special population for vancomycin
Caution in neonates/infants due to renal immaturity
Crosses placenta + present in breastmilk. Limited data. Use only if safer alternative not available.
Caution with older adults due to nephrotoxicity, ototoxicity, + neurotoxicity
Drug of choice for MRSA and C. difficile and severe infections
vancomycin
monitoring of vanco
renal function, serum drug levels, hydration
Oral formulation of vanco only indicated for
C. Diff
FOSFOMYCIN
MOA
___ killing
____ metabolism and elimination
Concentration-dependent killing
* Bactericidal in the urine
* Minimal hepatic metabolism
* Renal elimination (adjust dose prn)
FOSFOMYCIN indication
Only indicated for acute uncomplicated cystitis in females >18 yrs caused by E. coli or E. faecalis
fosfomycin should be taken
take without food
can cause dizzy and drowsy
Protein Synthesis Inhibitors
30s
antibiotics
Aminoglycosides
Tetracyclines
Protein Synthesis Inhibitors
50s
antibiotics
Macrolides
Lincosamides
Oxazolidinones
Aminoglycosides e.g.
- gentamycin
- tobramycin
- neomycin
- streptomycin