Topic 8-Penicillins Flashcards
Mechanisms of penicillin?
Interference with the cell wall synthesis by binding PBP (penicillin-binding-proteins) on the transpeptidase
Penicillin.
Bacteriocidal or bacteriostatic?
Time/Concentration/Other dependence?
Synergistic effect with what drug?
Bacteriocidal.
Time dependent (Need to give 3-4 dosing /continuous infusion)
Synergistic effect with aminoglycosides (like gentamicin)
Oral Penicillins (3)
Penicillin V, Amoxicillin, Oxacillin
Parental Penicillins (4)
Piperacillin, Penicillin G, Ampicillin, Amoxicillin (oral use ale)
Penicillin pharmacokinetics Protein binding? GI absorption? Tissue Distribution? Elimination? Pregnancy?
Binds Albumin extensively
Broken down quickly in GI
Distributes to near serum level in all tissues including breast milk, saliva, placenta, prostate (NO penetration into biliary tract, use ampicillin for this)
Eliminated in kidneys, short half life (30-80 mins)
Safest abx in pregnancy!!
Adverse effects of Penicillin (6)
- ) Hypersensitivity rxn
- ) Nephritis (high doses are administered)
- ) Seizures (high serum levels)
- ) Pseudomembrane colitis (caused by ampicillin)
- ) Morbiliform rash
- caused by amino penicillin use during a EBV/CMV
- Transient, not dangerous - ) Hematological rxn (hemolytic anemia/thrombocytopenia)
Basic penicillins (3)
Penicillin G, Penicillin V, and Penamecillin
Bacteria used for basic penicillins
Staphylococci Streptococci Gram Positive anerobe Pneumococci (30-40% resistance) N. Meningititis N. Gonorrhea (regional- asia=100% resistant, europe=30% resistant) Pasteurella Multocida Gram positive aerobes Actinomyces israeli Leptaspira Syphilis Lyme disease Gas gangrene caused by Antrhax Streptococcus pyogenes (tonsilar pharyngitis, erysipelas, scarlet fever) viridians (endocarditis)
What are the 4 main beta lactamase resistant antibiotics?
Methicillin, Nafcillin, Oxacillin, and Flucloxacillin
What are the beta lactamase resistant abx used for?
staphylococci (NOT MRSA) and streptococci and gram - aerobes
Two extended spectrum penicillins , also called?
Also called Aminopenicillins
- )Ampicillin
- )Amoxicillin
Aminopenicillins used for which bacteria
Basic penicillin bacteria list plus enterococci (ampicillin and gentamycin) gram positive and negative anaerobe gram negative aerobes proteus, salmonella, shigella, serratia, enterobacter E.coli, H. influenzae, Klebsiella Bacteriodes fragilis listeria monocytogenes pseudomonas aeruginosa listeria meningitis lyme disease H. pylori
Indications for Aminopenicillins
Upper/lower respiratory infections, UTI’s, bacteruria during pregnancy, and dentistry
Adverse effect of Ampicillin? Adverse effect of aminopenicillins
Ampicillin causes a morbitiform rash
Aminopenicillins can causes pseudomembrane colitis
Two families of broad spectrum penicillins
Carboxypenicillins and ureidopenicillins
carboxypenicillin abx
Ticarcillin
ureidopenicillin abx
piperacillin
Bacteria treated with broad spectrum penicillins
Streptococci
Enterococci
Gram - rods (H. influenza, E. Coli, Proteus, Salmonella, Shigella)
Coliform bacilli (Klebsiella, enterobacter, Pseudomonas aeruginosa, Serratia)
Gram + anaerobes
What beta lactamase can be added to aminopenicillins to make it more effective
Clavulanic acids
What beta lactamase inhibitor can be added to piperacillin to make it more effective? Which bacteria is it more effective against?
Tazobactam
Pseudomonas aeruginosa and gram negative anaerobe
Indications of broad spectrum penicillins
Severe pneumonia
Complicated UTI
Complicated abdominal infections
Complicated skin and soft tissue infections (diabetic foot)
Three beta lactamase and ABX pairs
- )Clavulanic acid and amoxicillin
- )Sulbactam and ampicillin
- )Tazobactam and piperacillin
