CLASSES OF ABX: CEPHALASPORINS Flashcards
First generation cephalasporins
4
CEFAlexin
CEFAzolin
CEFRADoxil
CEFRADine
Second generation cephalasporins
- Cefuroxime
- Cefoxitin
- Cefaclor
3rd gen
CefixIME
CefotaxIME
CeftazidIME
CeftriaxONE
4th
Cefepime
What spectrum is their activity?
Broad spectrum
Third and fifth generation cephalasporins
- All parenteral apart from oral cefixime
MOA
Prevent cell wall synthesis by binding to enzymes called penicillin binding proteins (PBPs).
What bacteria do cephalosporins have activity against?
Gram-positive + Gram-negative activity.
How are cephalosporins excreted?
renally
Indications
- Pneumonia
- Meningitis
- Gonorrhoea
- UTIs
can they penetrate the CSF
poorly unless meninges are inflamed
name the 2 cephalosporins that are suitable for infections of CNS e.g. meningitis
cefotaxime
ceftriaxone
Side effects
- Antibiotic-associated colitis (rare but more common with the 2nd and 3rd generation cephalosporins).
- Hypersensitivity
Hyperesensitivity to penicillins and cephalosporins relation
Patients with hypersensitivity to penicillin and other bet lactams should not receive cephalosporin due to cross sensitivity
this cephalosporin is commonly used in UTI infections, especially if the patient is pregnant, however it must be avoided in patients who have immediate hypersensitivity to penicillins. what is it?
cefalexin
what is the dose of cefalexin for lower UTI in pregnancy
500mg BD for 7 days
can ceftriaxone be given orally
No
given IV/ IM
can cefotaxime be given orally
no it is given IV,IM etc
can cefixime be given orally
yes it is only given orally
Interactions
Cephalosporins are nephrotoxic
Avoid other nephrotoxic drugs
monitoring requirements of ceftriaxone
FBC regularly during prolonged treatment
name some nephrotoxic drugs - so increased risk when given with cephalosporins
aciclovir
aspirin
amphotericin B
NSAIDs
ACEi
-platins
lithium
methotrexate
sulfasalazine
trimethoprim
zolendronate
vancomycin
