Cell Wall Inhibitors (Cephalosporins ) Flashcards
Features of Cephalosporins :
1) B- lactams
2) More resistant to B-lactamases
3) Semisynthetic
4) Structurally and functionally related to Penicillins
Cephalosporins Generations :
First,Second,third,fourth and advanced
First Generation of cephalosporins:
1) Cefazolin
2) Cephalexin
3) Cefadroxil
Antibacterial spectrum of first generation of cephalosporins :
They are resistant to Staphylococcal penicillinase ; Including MSSA but Not MRSA
First generation of Cephalosporins are …………….
Penicillin G substitutes
What are Second-generation of cephalosporins :
1) Cefotetan
2) Cefuroxime
3) Cefoxitin
4) Cefprozil
Anti-bacterial spectrum of second-generation of cephalosporins :
Wider to gram-negative spectrum :
1) H.influenza
2) Klebsiella
3) Neisseria app
4) Proteus
5) Moraxella catarrhalis
Second-generation of cephalosporins are ………………. Due to increasing in resistance
Nor first line
Third-generation of cephalosporins:
1) Cefotaxime
2) Ceftriaxone
3) Ceftazidime
4) Cefdinir
Antibacterial Spectrum of third-generation of cephalosporins :
Greater activity against gram-negative bacilli
The third-generation of cephalosporins are ………………. , there must be a caution of …………
Broad-Spectrum // Collateral damage
The third-generation of cephalosporins are drugs of choice for ……………
Meningitis
Fourth-generation Cephalosporins is :
Cefepime
Anti-bacterial spectrum of fourth-generation of cephalosporins :
1) effective against Strep and Staph species but not MRSA
2) Aerobic gram-negative bacilli including P.aeurogenosa
Fourth-generation of cephalosporins are ………………… anti-biotics
Broad-spectrum
What is the advanced-generation cephalosporins drug :
Ceftaroline
Anti-bacterial spectrum of advanced-generation cephalosporins:
Only B-lactam that is effective against MRSA
Advanced-generation of cephalosporins are ………………. Antibiotic that is indicated against …………
B-road-spectrum antibiotic / complicated skin MRSA infection & pneumonia
The limitation of using Ceftaroline :
Twice-daily dosing regimen
MOR of cephalosporins :
1) B-lactamases ( hydrolysis of the beta-lactam ring )
2) decreasing affinity of PBPs
Cephalosporins are susceptible to :
1) Penicillinase as Staph
2) Extended-spectrum beta lactamse ESBL as E.coli and klebsiella
What are ESBL ?
Plasmid-mediated,diverse, complex and rapidly evolving enzymes that share the ability to hydrolyse third-generation of cephalosporins and aztreonam
Administration of cephalosporins :
Either IV or IM , poor oral absorption
Oral cephalosporins as exceptions :
1)Cephalixen
2)Cefdinir
3) Cefixime