DR. MABANAG - CEPHALOSPORINS, CARBAPENEMS, MONOBACTAMS & BETA LACTAMASE INHIBITORS Flashcards
All cephalosporins have the same basic structure containing the _____________________which is a Dihydrothiazine ring attached to a β-lactam ring.
7-AMINOCEPHALOSPORANIC ACID NUCLEUS
● Very active vs. G(+) cocci: streptococci and staphylococci
● Limited activity vs G(-) such as Proteus mirabilis, E. coli, Klebsiella pneumoniae (Mnemonic: PEcKs first)
First Generation Cephalosporins
First Generation Cephalosporins
● Examples (Mnemonic: FADer, help me FAZ my PHarmacology exam)
○ CeFADroxil
○ CeFAZolin
○ CePHalothin
○ CePHapirin
○ CePHradine
○ CePHalexin
*WITH ADDITIONAL G- COVERAGE
○ H. influenza
○ Enterobacter
○ Neisseria
○ Proteus mirabilis
○ Escherichia coli
○ Klebsiella pneumoniae
○ Serratia marcescens
● Mnemonic: HEN PEcKs
Second Generation Cephalosporins
Second Generation Cephalosporins
FAMily FOX FURing TEa
○ CeFAMandole
○ CeFOXitin
○ CeFURoxime
○ CefoTEtan
Second Generation Cephalosporins
● Mnemonic: “FAC! LORA the PROfessional AZOLE is still on the FONe!”
○ CeFAClor
○ LORAcarbef
○ CefPROzil
○ CefmetAZOLE
○ CeFONicid
● Expanded G(-) coverage, some are able to cross BBB
● All penetrate well into the CSF, so for CNS infections these are usually used
ThirdGenerationCephalosporins
ThirdGenerationCephalosporins
● Mnemonic: “FEnge PO ng PERA to FIX my 3
(TRI) TTTTv”
○ CeFEtamet
○ CefPOdoxime
○ CefoPERAzone
○ CeFIXime*
○ CefTRIaxone
○ CefTazidime—most widely used in the
Philippines
○ CefoTaxime
○ CefTizoxime
○ CefTibuten
●P. aeruginosa
Enterobacteriaceae
methicillin-susceptible S. aureus
S. pneumoniae
● Penetrates well into the CSF
FourthGenerationCephalosporins
CEFEPIME
FourthGenerationCephalosporins
● added activity against MRSA
● Unlike 4th gen cephalosporin—no activity against P. aeruginosa
FifthGenerationCephalosporins
CEFTAROLINE
FifthGenerationCephalosporins
○ Both FDA-approved for treatment of complicated intra-abdominal infections & UTIs
○ Relatively new antibiotics
● Ceftolozane + Tazobactam
● Ceftazidime + Avibactam
These are the newer β-lactam inhibitors
● Tazobactam & Avibactam
used for brain infections because they penetrate well into the CSF
Cefuroxime, 3rd and 4th generation
cephalosporins
Used for treatment of UTI, staphylococcal and streptococcal infections including cellulitis and soft tissue abscess, surgical prophylaxis
FIRST GEN
Used primarily for sinusitis, otitis, LRTIs & community-acquired pneumonia
SECOND GEN
Used for serious infection requiring IV therapy (e.g. meningitis, neutropenic fever)
3RD GEN
Used for infections caused by Pseudomonas aeruginosa and Enterobacter
4TH GEN
Used for MRSA infection
5TH GEN - CEFTAROLINE
Used for treatment of complicated intra-abdominal infections and urinary tract infections
Cephalosporins + Beta-Lactamase Inhibitor
Adverse Reactions of Cephalosporins
ALLERGY
GI DISTURBANCES
HYPOPROTHROMBINEMIA & BLEEDING DISORDER
DISULFIRAM LIKE INFECTIONS (flushing, tachycardia, hypotension, nausea, dizziness) - Due to inhibition of the
enzyme acetaldehyde dehydrogenase
DRUGS THAT CAUSE THE DISULFIRAM-LIKE REACTIONS:
● Metronidazole
● Cefotetan
● Cefamandole
○ Cefotetan and Cefamandole are 2nd gen cephalosporins
● Cefoperazone (3rd gen cephalosporin)
● Disulfiram
● broadest-spectrum of all beta-lactam abx
○ Excellent activity against both Gram(+) and (-), aerobic and anaerobic bacteria
○ Good activity against Pseudomonas aeruginosa & Bacteroides fragilis (except Ertapenem)
‐ Does not have activity against MRSA
CARBAPENEMS
FIRST CARBAPENEM
inactivated dehydropeptidase in renal tubules, resulting in low urinary concentrations
○ Always administered together with an inhibitor of dehydropeptidase, Cilastatin, to prolong its half-life
IMIPENEM
competitive inhibitor of renal tubular
dehydropeptidase, resulting in the inhibition of cleavage of Imipenem
CILASTATIN
ADVERSE EFFECT OF CARBAPENEMS
-SEIZURE
-ALLERGY
-GI DISTRESS