Cephalosporins Flashcards
Cephalosporin MOA
- Same as penicillins; bacteriocidal
Resistance to Cephalosporins is primarily through…
- Beta-lactamase production
- May alter affinity or lack of PBP
First Generation Cephalosporins
Oral – cephalexin and cefadroxil
IV/IM - cefazolin
First Generation Cephalosporins are active against….
- Gram Positive Cocci (Not enterococci or MRSA)
- Some gram negative bacilli (E. coli, proteus, klebisella)
T/F: First Generations can penetrate the CNS
- Flase
First Generations are the drug of choice for…
Nothing
Cefazolin for surgical prophylaxis
Always second line
What is the difference between cephamycin and cephalosporins?
- Structure wise
- Cephamycins –> Oxygen
- Cephalosporins –> Sulfur
What structure does cephalosporins have?
- Beta-lactam ring
Oral Second Generation Cephalosporins
- Cefuroxime axetil
- Cefprozil
IM/IV Second Generation Cephalosporin
- Cefuroxime
Second Generation Cephamycin
- Cefoxitin
Second Generation Cephalosporins are active against….
- Gram Positive Cocci (Not enterococci or MRSA)
- Some gram negative bacilli (E. coli, proteus, klebisella)
- More coverage of gnb, but not pseudomonas aeurginosa
Cephamycins are used in….
used in mixed aerobic/anaerobic infections
–> in the gut –> ruptured appendix –> also seen in diabetic foot infections
Third Generation Cephalosporins
- Ceftotaxtime
- Ceftriaxone
- Ceftazidime
- Cefiixime
Cefoxatime and Ceftriaxone covers…
- Gram negative cocci, but do not cover Pseudomonas aeuroginosa
Ceftazidime Spectrum
- Covers/reserved for pseudomonas aeuroginosa
- Lose alot of gram positive activity
IV/IM Route of Admin 3rd Gen Cephalosporin
Cefotaxime, Ceftriaxone and Cetazidine
Oral Agent 3rd Gen Cephalosporin
- Cefixime
3rd Generation Cephalosporin Spectrum of Activity
Decreased activity against gpc except Strep. pneumoniae
Enhanced activity against gnb
In regards to absorption, what is the difference between 1stt, 2nd and 3rd gen cephalosporins?
Ability to penetrate the CNS (1st and 2nd don’t, but 3rd do)
Fourth Generation Cephalosporins
- Cefepime
- Ceftaroline
- Ceftobiprole
Cefepime Spectrum, Use
Enhanced activity against Enterobacter and Citrobacter; active against Ps. Aeruginosa –> use always reserved in hospital special permission to use
Ceftaroline and Ceftobiprole Spectrum
activity against MRSA, ampicillin sensitive E. faecalis and penicillin resistant S. pneumoniae
Fourth Gen Cephalosporin Spectrum
- Broad spectrum
Adverse effects of cephalosporins
Hypersensitivity
Diarrhea
Skin rash
Other- fever, granulocytopenia, hemolytic anemia
Biliary pseudolithiasis - ceftriaxone
Cephalosporin Elimination
- Eliminated through the biliary system
Carbapenems are related to….
- Beta-lactams
Carbapenems Example
Imipenem-cillastatin
Meropenem
Ertapenem
I am ME
Can imipenem be used alone?
Imipenem is never given alone –> always given with cilistan
Cilistatin is not anti-biotic
Imipenem and Meorpenem have… activity.. that covers
Similar
gram positive, gram negative, including Pseudomonas, and anaerobic organisms
Ertapenem Dose and Activity
Ertapenem – long half-life (once daily); poor activity against Enterococcus sp and P. aeruginosa
Monobactam Structure, Resistance, Example and Spectrum
Monocyclic beta-lactam ring
Resistant to many beta-lactamases
Aztreonam – not available in Canada
Active against gnb including Ps. Aeruginosa
