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Penicillin Mechanism of Action: Blocks cell wall synthesis by inhibition of peptidoglycan cross-linking

Ampicillin Mechanism of Action: Blocks cell wall synthesis by inhibition of petidoglycan cross-linking

Ticarcillin Mechanism of Action: Blocks cell wall synthesis by inhibition of peptidoglycan cross-linking

Piperacillin Mechanism of Action: Blocks cell wall synthesis by inhibition of peptidoglycan cross-linking

Imipenem Mechanism of Action: Blocks cell wall synthesis by inhibition of peptidoglycan cross-linking

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Aztreonam Mechanism of Action: Blocks cell wall synthesis by inhibition of peptidoglycan cross-linking

Cephalosporins Mechanism of Action: Blocks cell wall synthesis by inhibition of peptidoglycan cross-linking

Bacitracin Mechanism of Action: Block peptidoglycan synthesis

Vancomycin Mechanism of Action: Block peptidoglycan synthesis

Chloramphenicol Mechanism of Action: Block Protein synthesis at 50s ribosomal subunit

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Erythromycin/Macrolides Mechanism of Action: Block Protein synthesis at 50s ribosomal subunit

Lincomycin Mechanism of Action: Block Protein synthesis at 50s ribosomal subunit

Clindamycin Mechanism of Action: Block Protein synthesis at 50s ribosomal subunit

Streptogramins (quinupristin,dalfopristin)

Mechanism of Action: Block Protein synthesis at 50s ribosomal subunit

Aminoglygosides Mechanism of Action: Block protein synthesis at 30s ribosomal subunit

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Tetracyclines Mechanism of Action: Block protein synthesis at 30s ribosomal subunit

Quinolones Mechanism of Action: Block DNA topoisomerases

Rifampin Mechanism of Action: Block mRNA synthesis

Polymyxins Mechanism of Action: Disrupt bacterial/fungal cell membranes

Amphotericin B Mechanism of Action: disrupt fungal cell membranes

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Nystatin Mechanism of Action: disrupt fungal cell membranes

fluconazole (azoles) Mechanism of Action: disrupt fungal cell membranes

Pentamidine Mechanism of Action: unknown mechanism of action

Penicillin 2 forms G (IV form) // Penicillin V (oral)

Penicillin (mechanism of action)1. Binds penicillin-binding proteins 2. Blocks

transpeptidase cross-linking of cell wall 3. Activates autolytic enzymes

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Penicillin (clinical use) bactericidal for G+ cocci, G+ rods, G- cooci, and spirochetes. Not penicillinase resistant

Penicillin (toxicity hypersensitivity reactions, hemolytic anemia

Methicillin, nafcillin, dicloxacillinsame mechanism of action as penicillin. Narrow spectrum; Penicillinase resistant due to bulkier R

group

Methicillin, nafcillin, dicloxacillin clinical use --> treat staph aureus

Methicillin (toxicity) interstitial nephritis

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methicilin, nafcillin, dicloxacillin (toxicity)

hypersensitivity reactions

Ampicillin, Amoxicillin Same mechanism of action as penicillin. Wider spectrum; penicillinase sensitive

What can you combine w/ ampicillin or amoxicillin to enhance spectrum

clavulanic acid (penicillinase inhibitor)

remember amOxicillin has greater Oral bioavailability than ampicillin

Ampicillin, amoxicillin (clinical use)

ampicillin / amoxicillin HELPS kill enterococci (Haemophilus influenzae, Escherichia coli, Listeria monocytogenes, Proteus mirabilis, Salmonella,

enterococci)

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Ampicillin, amoxicillin (toxicity) Hypersensitivity reactions; ampicillin rash; pseudomembranous colitis

Carbenicillin, Piperacillin, ticarcillin

Same mechanism of action as penicillin; extended spectrum - pseudomonas species and G- rods;

susceptible to penicillinase; use w/ clavulanic acid; can cause hypersensitivity reaction

Cephalosporins (mechanism of action)

beta lactam drugs that inhibit cell wall synthesis but are less susceptible to penicillinases; bactericidal

1st gen cephalosporin G+ cocci, PEcK (Proteus mirabilis, E. coli, Klebsiella pneumoniae)

2nd gen cephalosporinG+ cocci, HEN PEcKS (Haemophilus influenze,

Enterobacter aerogenes, Neisseria species, Proteus mirabilis, E. coli, Klebsiella pneumoniae, Serratia

marcescens

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3rd Generation cephalosporin serious G- infections resistant to other Beta lactams; meningitis (most penetrate BBB)

Pseudomonas ceftazidime (3rd gen ceph)

Gonorrhea Ceftriaxone (3rd Gen ceph)

4th gen cephalosporin increased activity against pseudomonas G+ organisms

Cephalosporin toxicityhypersensitivity, increased nephrotoxicity of aminoglycosides, disulfiram-like reactions w/

ethanol

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AztreonamA monobactam resistant to Beta lactamases. Inhibits cell wall synthesis - synergistic w/ aminoglycosides /

no cross-alergenicity w/ penicillins

Aztreonam (clinical use)

G- rods (klebsiella species, Pseudomonas species, Serratia species) // no activity against anaerobes. // used for penicillin-allergic patients and those w/

renal insufficiency who can't tolerate aminoglycosides / usually nontoxic - can cause GI

upset

Imipenem / cilastatinBroad-spectrum, beta lactamase-resistant / always given w/ cilastatin (inhibits renal dihydropeptidase 1 --> decrease imipenem inactivation in renal tubules)

Imipenem / Cilastatin (clinical use) G+ cocci, G- rods, and anaerobes

DOC for enterobacter imipenem / cilastatin

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Imipenem / cilastatin (toxicity GI distress, skin rash, and CNS toxicity (seizures) at high plasma levels

Vancomycin (mechanism of action)

inhibits cell wall mucopeptide formation by binding D-ala D-ala portion of cell wall precursors / Bactericidal / resistance occurs w/ amino acid

change of D-ala D-ala to D-ala D-lac

Vancomycin (clinical use)used for serious, G+ multidrug-resistant organisms. including staph aureus and Clostridium difficile

(pseudomembranous colitits)

Vancomycin tocicityNOT - Nephrotoxicity, Ototoxicity, and

Thrombophlebitis, diffuse flushing -->"red man syndrome" (can prevent w/ pretreatment w/ antihistamines and slow infusion rate)

Aminoglycosides (streptomycin, gentamicin, tobramycin, amikacin) / bactericidal

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Tetracyclines bacteriostatic

30S protein synthesis inhibitors Aminoglycosides and tetracyclines

50S protein synthesis inhibitorsCELL / Chloramphenicol, Erythromycin,

Lincomycin, cLindamycin // all are bacteriostatic