Pharm: Cell wall synthesis inhibitors Flashcards
What are the five types of penicillins?
- Penicillin G
- Aminopenicillins
- Anti-staph
- Anti-pseudomonas
- Combo with beta-lactamase
What are the components of augmentin?
amoxicillin and clavulanate
What are the components of unasyn?
ampicillin and sulbactam
What are the components of zosyn?
piperacillin and tazobactam
What property makes nafcillin and dicloxacillin good for most staph?
It has resistance to the beta lactamase produced by s. aureus
What is piperacillin good for?
pseudomonas, klebsiella and other GRAM NEGATIVE RODS.
NOT effective against MRSA
Is piperacillin resistant to beta lactamase?
No, it’s degraded
What is penicillin G good for?
Strep (pharyngitis/pneumonia/meningitis/endocarditis), enterococcus, meningococcus, and syphilis. Also oral/dental infections. Also to prevent GAS rheumatic fever
What does the procaine suspension of penicillin do?
IM, lasts 1-2 days
What does the benzathine suspension do?
IM, lasts for 1-4 WEEKS!
What is the formulation of ampicillin?
IV/PO
What is the formulation of amoxicillin?
ONLY po (it’s got an O in the name!)
When would you use ampicillin?
otitis media, neonatal sepsis, URI
What does amoxicillin have that ampicillin does not?
amoxicillin has more oral availability and a wider spectrum. It’s also less likely to cause diarrhea
Which tx for MSSA is oral/IV?
dicloxacillin is oral
Nafcillin and oxacillin are IV and for more serious infections
Which one of the MSSA drugs is NOT effective against gram - rods?
nafcillin
What form does piperacillin come in?
IV ONLY
What are the beta lactams not that good for?
The SPACEK creatures
Why don’t we use methacillin anymore?
Because it causes allergic interstitial nephritis
What’s different about the structure of monobactams (aztreonam)?
It only has one ring and is less likely to cause an allergic cross reaction
Why do cephalosporins have a wide spectrum?
Resistant to beta lactamases
What do cephalosporins NOT cover?
enterococcus and listeria
What do first generation cephalosporins cover?
staph and strep
What do later generation cephalosporins cover?
GNR
What is the name of the first generation cephalosporin?
cefazolin
What does cefazolin cover?
Strep and Staph. Good for UTIs (covers some E coli), and surgical prophylaxis
What form does cefazolin come in?
Not PO! But cephalexin is PO
When would you use ceftriaxone?
MENINGITIS, also serious pneumonia
Which bugs do ceftriaxone cover?
Strep (most common cause of meningitis)
Strep pneumo (serious pneumonia)
Can also cover MSSA and GNRs
What is the other 3rd gen cephalosporin?
Ceftazidine
When would you use ceftazidine?
It’s better at GNR and PSEUDOMONAS***
Patients who are given cephalosporins are at increased risk of getting what infections?
fungal infections
What is the broadest spectrum Abx we have?
meropenem
What does meropenem not cover?
MRSA. Covers GPC, GNR, pseudomonas
What type of situation would we want to use meropenems for?
abdominal infections
What does aztreonam cover?
Aerobic, GNR (E coli and pseudomonas)
What situations would you use aztreonma?
UTI or intraabdominal infection. However, coverage is pretty narrow so you need to be sure that the infection is only from aerobic GNRs!
Think SPACEK
Describe the structure of vancomycin. How does this work?
No beta lactam ring–huge structure
–It inhibits cell wall cross linking by altering COOH of D-ala-D-ala
When would you use vancomycin acid from MRSA?
Coagulase negative staph
enterococcus
strep pneumo that’s resistant
C difficile (po)
What is a serious contraindication to daptomycin?
pneumonia–interferes with surfactant in lungs
Also, don’t use with a statin
What is a side effect of daptomycin?
myopathy
In what formulation does daptomycin come
IV only
What is best for enterococcus?
penicillin. Much better than cephalosporins
What do you use for listeria?
Ampicillin or penicillin
When would you use cefazolin?
strep/staph covered but also oral anaerobes and GNR: use in abdominal infections
Are cephalosporins effective in MRSA?
NO
Why do you add vancomycin to the empiric treatment of strep pneumo?
Because 10% of pneumococcus is resistant to ceftriaxone
What is the only cephalosporin that we can use for MRSA?
cefarolin(5th generation)
What do you use to treat N. Meningitidis?
Penicillin G–it has excellent penetration of the CSF
Side effect of vanc?
red man syndrome, with large release of histamine. Need to infuse slowly over 60 minutes
When would you use Daptomycin?
Drug of last resort in VRE
