Antimicrobials: Cell wall synthesis inhibitors Flashcards
Bactericidal drugs
All cell wall synthesis inhibitors, aminoglycosides, Ketolides, quinolones, nitrofurantoin, sulfonamides + DHF reductase inhibitors, Metrondiazole
Bacteriostatic drugs
all protein synthesis inhibitors
Sulfonamides alone
Beta lactams
Penicillins Cephalosporins Monobactams Carbapenems B lactamase inhibitors
Other cell wall synthesis inhibitors
Glycopeptides (Vanco), lipopeptides, bacitracin and cycloserine
MOA of penicillin
Bind to penicillin binding proteins, prevent transpeptidation, inhibits cross linking of bacterial cell wall
Excretion of penicillin
Excreted unmetabolized by kidney
Resistant mechanisms of bacteria to penicillin
Beta lactamases, mutation of penicilin binding protein to decrease binding, upregulation of efflux channels
Adverse effects of penicillin
Hypersensitivity, GI upset
DOC for C. Dif
Metronidazole
What can help prevent resistance to penicillin
Beta lactamase inhibitors: clavulanic acid, sulbactam, tazobactam
Probenecid
blocks secretion of penicillin into urine and increases half life
Main drug for syphilis
Penicilin G
Methicilin
Beta lactamase resistant penicillin
Not used clinically due to risk of interstitial nephritis
Aminopenicillins
Beta lactamase sensitive– pair with beta lactamases inhibitors
Broad spectrum
Ampicillin
Active against G+ and G-
Poor absorption orally so given IV
Used for suspected listeria meningitis and aspiration pneumonia
Amoxicillin
Good oral absorption
Used for otitis media, community acquired pneumonia, sinusitis, GI/GU infections, H Pylori
Drug used in prophylaxis of dog, cat and human bite
Augmentin
Amoxicillin + Clavulanic Acid
Combine aminopenicillins with what to increase synergy and decrease resistance
Amingoglycosides (Ex. gentamicin)
Extended spectrum penicillins
Beta lactamase sensitive
Primarily used for severe nosocomial infections
Tx/prophylaxis of group B strep in pregnancy
Penicillin
Route of admin for Penicillin G
IV
Route of admin for Penicilin V
Oral
Piperacilin and ticarcillin
Against anaerobe bacteria such as pseudomonas
Cephalosporins
Similar MOA as penicillin
1st generation cephalosporin
Used primarily for surgical prophylaxis
G+ mostly and some G- bugs for UTI
Have “ph” in the name
Cefazolin + Cephalexin
2nd generation cephalosporin
More G- and still G+
Cefuroxime
Used mostly for respiratory bugs
Hardly ever used as first line treatment
3rd generation cephalosporin
Systemic and CSF entry–good for tx of meningitis
Treatment of community and hospital acquired pneumonia
First line treatment for gonorrhea
First line tx for ghonorrhea
IM ceftriaxone: 3rd generation cephalosporin
4th generation cephalosporin
Cefepime Resistant to most Beta lactamases Penetrates CSF and good against pseudomonas Broad spectrum Can enter CNS--can tx meningitis
5th generation cephalosporin
Can treat MRSA
ceftaroline
Adverse effects of cephalosporins
Hypersensitivity
Monobactams
Active against G- rods only including pseudomonas
No cross allergy from penicillin or cephalosporins
Aztreonam
Can penetrate CSF–can tx meningitis
Carbapenems
-penem
Active against anaerobes, G+ and G- rods
Broad spectrum
Can penetrate CSF
Big gun antibiotics–can treat serious infections, meningitis, sepsis
Imipenem
Must be co-administered with cilastatin to decrease renal toxicity
Can cause seizures
Vancomycin
Glycoprotein antibiotic active only against G+ bacteria
Resistant to beta lactamases
IV only
Main indication for vancomycin
Blood stream infection due to MRSA
Other indications for vancomycin
Meningitis, MRSA osteomyelitis, endocarditis
Adverse effects of vancomycin
red man syndrome, thrombophlebitis at admin site
Bacitracin
Prevents dephosphorylation of lipid carrier
Used predominantly as topical agent due to severe nephrotoxicity when given IV
Used primarily for skin infections
Deptomycin
Active against G+ cell wall
Active against vanco resistant strains
MRSA coverage especially bacteremia
Do not use deptomycin for
Pneumonia–antagonized by surfactant
Major SE of deptomycin
Myopathy