Topic 9-Cephalosporins Flashcards
Mechanism of action
Inhibits transpeptidase by binding PBP
First generation cephalosporin parenteral drugs
cefazoline cefalotin
First generation cephalosporin oral drugs
cefalexin cefadroxil
First generation spectrum and indication
Gram positive bacteria, strong effect Strong effect for staphylococcus Used in clinic as prophylaxis, pre-aspiration meds to avoid gram + infections Used in respiratory/skin infections (maybe UTI)
Second generation cephalosporin parenteral drugs
cefuroxime cefamandole cefoxitin
Second generation cephalosporin oral drugs
cefuroxime-axetil cefaclor
Second generation cephalosporin spectrum and indications
good effects against Gram -/+ (better against gram -) With cephalosporin 1 drugs, has best effects against staph H. influenzae, Neisseria, and Serratia Indications include mild UTI airway infection
What bacteria is cefuroxime good against
H. influenzae
What is cefoxitine good for
mild/moderate/severe poly-infection and bacillus fragilis Good effect against oral cavity anaerobes
Third generation cephalosporin parenteral drugs
ceftriaxone cefotaxime cefoperazone ceftazidime
Third generation cephalosporin oral drugs
ceftibuten cefixime
Third generation cephalosporin spectrum
Gram - best effect with 4th and 5th generation cephalosporins Worst effect for Gram +
Third generation cephalosporin indications
-Reserve ABX -Used in pneumococcus ABX resistance -oral-used in UTI -Pyelonephritis, 1st choice compound since fluroquinolones are now resistant -CNS, 1st choice treatment of meningitis -pseudomonas aeruginosa
Which bacteria is Ceftazidime used for
pseudomonas
Which bacteria is cefoperazone used for
pseudomonas
Fourth generation cephalosporins parenteral drug
cefepime
What is the spectrum of fourth generation cephalosporins
Effective against Gram - like third and fifth generation and some MRSA effect/Gram + effect
What is cefepime used for
pseudomonas
What are the fifth generation cephalosporin parenteral drugs
ceftolozane ceftaroline
What are the spectrum of fifth generation cephalosporins
Effective against Gram - like third and fourth generation and strong MRSA effect/Gram + effect
What is ceftolozane used for?
pseudomonas, acetobacter, Gram - pneumonia, UTI, and abdominal infections
What is ceftaroline used for?
Gram -, MRSA, and community acquired skin infections
Cephalosporin pharmacokinetics (5 major points)
No oral absorption Bad distribution Good penetration 3rd generation has excellent penetration (therapeutic levels reached in gallbladder) 3rd generation has good therapeutic levels for meningitis
Cephalosporin administration
8-12 hours given
How often is cefotaxime given
3-4 times a day (taxis are fast so has faster degradation)
What antibiotics are given once a day
ceftriaxone, ceftibuten, and cefixime
Where is cephalosporins metabolized
kidneys
Besides the kidney’s where is ceftriaxone and cefoperazone eliminated
the bile (40-50% of the time)
Side effects of cephalosporins
Non-toxic ABX Allergy (cross allergy with penicillin so if you have a penicillin allergy, high chance of being allergic to cephalosporins) High serum levels causes epileptic serizures Hemolytic anemia/thrombocytopenia GI effect=diarrhea, biliary tract alcohol intolerance Disulfiram like effect
Which two drugs cause alcohol interolerance?
cefoperazone and cefamandol (Think music cause of opera and mandolin)
Disulfiram like effect is
inhibited aldehyde dehydrogenase causes acetyl aldehyde build up leading to nausea, vomiting, high blood presure, and flushing
