Bacterial Cell Wall synthesis inhibitors (ic8) Flashcards
4 types of Beta lactams
Penicillins
Cephalosporins
Carbapenems
Monobactam
4 types of Penicillins
1) Natural Penicillins
2) Penicillinase resistant Penicillins
3) Amino Penicillins
4) Anti-pseudomonal Penicillins
Thought process of Penicillins (examples, which has good oral F, (+) or (-) coverage, hence use: )
Natural Penicillins
Examples are Penicillin V, Penicillin G.
Only Penicillin V has good oral bioavailability
Have gram (+) and gram (-) coverage, but susceptible to Beta-lactamase / Penicillinase producing bacteria eg. Staphs / MSSA, hence use:
Penicillinase resistant Penicillins
Example is Cloxacillin
Good oral bioavailability
Only Gram (+), can cover MSSA
1 and 2 mainly cover Gram (+), hence use:
Aminopenicillins (+ Beta lactamase Inhibitors)
Examples are Amoxicillin (+ Clavulanic acid), Ampicillin (+ Sulbactam)
Amoxicillin has better oral bioavailability than Ampicillin
Gram (+) and wider Gram (-) coverage
Cannot cover Pseudomonas or Klebs, hence use:
Anti Pseudomonal Penicillins
Example is Piperacillin (+ Tazobactam)
Can cover Pseudomonas and Klebs
Cephalosporins examples (How many generations, what are the examples)
First gen
Cephalexin, Cephazolin
Second gen
Cefuroxime
Third gen
Ceftazidime
Ceftriaxone
Fourth gen
Cefepime
Fifth gen
Ceftaroline
Cephalosporin trend moving down the generation (4 points)
Administration
Oral for 1st (except Cefazolin) and 2nd, Parenteral for 3rd and 4th
Activity for Gram (-) increases
CSF penetration increases
Beta-lactamases: Can use better
Thought process for Cephalosporins (Examples, Coverage, Administration)
First gen
Examples are Cefazolin, Cephalexin
Coverage is (+), similar to Natural Penicillins and Penicillinase resistant Penicillins
Good oral F, except Cefazolin
Second gen
Example is Cefuroxime
Coverage is (-), not active for Pseudomonas
Good oral F
Third gen
Example is Ceftazidime, Ceftriaxone
Coverage is (+) and (-)
Parenteral
ONLY Ceftazidime can cover Pseudomonas
Ceftazidime is the only cephalosporin with Hepatic impairment
Fourth gen
Example is Cefepime
Parenteral
Covers Pseudomonas
Fifth gen
Example is Ceftaroline
Parenteral
Can cover LAME (Legionella, Atypicals, MRSA, Enterococcus)
Adverse effects for Cephalosporins (2 points)
Hypersensitivity
Low cross reactivity between Penicillins and Cephalosporins (1%)
DONT GIVE if have serious rxn to Penicillins
GI Symptoms
Vomiting, diarrhea
CDAD (C.Diff Associated Disease, due to lack of normal gut flora)
Indication for Carbapenems
Used for Extended Spectrum Beta Lactamases (ESBL) Gram (-)
What is the role of Cilastatin? What is Cilastatin used with and what is the effect?
(DHP1 inhibitor)
Prevent hydrolysis of Imipenem, recover more active form of Imipenem + Increase duration of action
Examples of Carbapenems
Which Carbapenem cannot be used fro Pseudomonas?
Imipenem + Cilastatin
Cilastatin (DHP1 inhibitor)
Prevent hydrolysis of Imipenem, recover more active form of Imipenem + Increase duration of action
Meropenem
Ertapenem
DONT USE for Pseudomonas
Adverse reactions of Carbapenems (3 points)
Hypersensitivity
Cross reactivity to Penicillin
GI symptoms
Diarrhea, vomiting
CDAD
Neurotoxicity
For renal impaired patients
Monobactam-Aztreonam (Coverage, Administration)
Only Gram (-) coverage
No activity against Gram (+) and Anaerobic
Administered parenterally
No cross reactivity to Penicillins
MOA of Vancomycin
Inhibit Transglycosylation (formation of single chain with NAM and NAG)
Characteristics of Vancomycin (Coverage, Clearance, administration
Gram (+)
Can use against MRSA
Renally cleared
IV, Poor oral (but still used first line for CDAD)
Adverse reactions for Vancomycin (3 points)
Thrombophlebitis
Red man syndrome
Rash on face, neck and upper torso
Prolong duration of infusion to 1-2hrs
Nephrotoxicity, Ototoxicity
