Pharm2210 l18 Drug Study PDF

Pharm2210 l18 Study online at https://quizlet.com/_f7r51m 1. B-lactams penicillins and cephalosporins 2. Differences in an- Can be explained by the interactions of B-lactam drugs tibacterial speci- and various penicillin binding proteins in bacteria ficity 3. B-la...

Pharm2210 l18 Study online at https://quizlet.com/_f7r51m 1. B-lactams penicillins and cephalosporins 2. Differences in an- Can be explained by the interactions of B-lactam drugs tibacterial speci- and various penicillin binding proteins in bacteria ficity 3. B-lactams 1 - Amoxicillin (synthetic, broad, no b-lactamase resistance) penicillins Clavulanic acid (synthetic, b-lactamase inhibitor) 4. Penicillin Phar- Acid stability varies macokinetics Lipid insoluble -do not enter mammalian cells -cross blood/brain barrier only if meninges are inflamed Most penicillins eliminated renally v quickly 5. Penicillin resis- Alterations in PBPs > decrease drug binding and antibac- tance terial activity Prevent B-lactams from accessing and transversing pore channels and reaching PBPs in cell membrane of G- bacteria Produce B-lactamase >inactive B-lactams **augmentin (amoxicillin + clavulanic acid) 6. Penicillin ADR opening B-lactam ring > benzylpenicilloyl Type 1&2 sensitivity reactions Superinfection (eg. Candidiasis) occurs w prolonged use 7. B-lactams: 5th gen: expanded G+, inc. MRSA; common G- Cephalosporins Binding w ^affinity (ceftaroline) 8. Cephalosporins Acid stable Pharmacokinetic Most administered parenterally; few orally Distribution: extracellular fluid; some cross B/B barrier to treat meningitis Excret. mostly renal tubular secretion 9. Cephalosporin Similar to penicillins ADR Cross reactivity between penicillins and cephalosporins causes ADR 1/3  Pharm2210 l18 Study online at https://quizlet.com/_f7r51m -open b-lactam ring> cephalosporoyl unrelated to ADR -similarity of sidechains between 1&2gen ceph and peni- cillins 10. bacterial protein Initiation synthesis >tRNA binding >Peptide bond formation >translocation >elongation cycle 11. Bacterial protein Inhibit 1 of 4 key steps in bacterial protein synth synth inhibitors Most = bacteriostatic (aminoglycosides bactericidal) 12. Aminoglyco- inhib: initiation sides MOA: [30s] inhibit codon-anticodon interaction: cause mRNA misreading 13. Tetracyclines Inhib: tRNA binding MOA: [30s] inhib aa-tRNA binding to A site 14. Amphenicols Inhib: transpeptidation MOA: [50s] inhib peptide bond formation 15. Antibacterial Inhib: Elongation &/or translocation macrolides MOA: [50s] prevent transfer of tRNA w the growing peptide from A site to P site 16. Bacterial PSIs: -bactericidal Aminoglyco- -G- & G+ sides - time + [conc ] dependant - AUC:MIC Pharmacokinetics -admin intramuscular or intravenous -eliminated glom filtration Ototoxicity -hearing loss and impaired vestibular function Nephrotoxicity -accum in prox tubular epithelial cells 17. 2/3  Pharm2210 l18 Study online at https://quizlet.com/_f7r51m Bacterial PSIs - Broad spec: G- & G+ tetracyclines Bacteriostatic Generally oral admin, but also parenterally GI disturbance -direct irritation + mod of gut flora w prolonged use Ca chelation -accumulation in teeth and bones staining and deformities - avoid kids and pregnant (Cate- gory D) 18. Bact. PSIs - Am- Broad spec: G-&G+ phenicols Bacteriostatic Pk: Chloramphenicol -rapid absorption orally -hapatic clear (UGT2B7) Bone marrow suppression -idiosyncratic; pancytopenia= dcrease all blood cell ele- ments Grey baby syndrome -insufficient Glucuronidation + excretion in newborns 19. Bact PSIs Similar spectrum to penicllin - useful alternatives - antibact. Concentrated w in phagocytes - enhance intracellular Macrolides killing of bacteria Oral or IV admin Substates for + inhibitors of CYP3A4- drug-drug interac- tion GI disturbance 20. Mech resistance Aminoglycosides: drug mod to bact PSIs Tetracyclines: active efflux of drug; drug mod Chloramphenicol: target mod (rRNA/proteins) Macrolides: target mod (rRNA/proteins); drug deg by es- terases 3/3