Flashcards in Fiser Absite. Ch 06-07. Antibiotics. Medicines And Pharmacology Deck (112)
What is the difference between an antiseptic and a disinfectant?
antiseptic kills and inhibits organisms on body. disinfectant kills and inhibits organisms on inanimate objects
What is the difference in coverage for iodophors like Betadine and Clorhexidine?
Both cover GPCs, GNRs but Chlorhexidine is better for fungi
What is the mechanism of action for penicillins, cephalosporins, carbapenems, monobactams and vancomycin?
inhbition of cell wall synthesis
What is the mechanism of action of tetracycline, aminoglycosides and linezolid?
inhibitors of the 30s ribosome and protein synthesis
What is the mechanism of action of erythromycin, clindamycin, chloramphenicol, Synercid?
inhibitors of the 50s ribosome and protein synthesis
What is the mechanism of quinolones?
inhibitor of DNA helicase (DNA gyrase)
What is the mechanism of rifampin?
inhibitor of RNA polymerase
What is the mechanism of metronidazole?
Produces oxygen radicals that breakup DNA
Whast is the mechanism of sulfonamides?
PABA analogue, inhibit purine synthesis
What is the mechanism of trimethoprim?
inhibits dihydrofolate reductase, inhibits purine synthesis
____ have irreversible binding to ribosome and are considered bactericidal
What is the most common method of antibiotic resistance?
transfer of plasmids
How is the mechanism of resistance to methiclllin or vancomycin developed?
mutation in cell wall binding protein
How is the mechanism of resistance to gentamicin developed?
resistance due to modifying enzymes leading to decrease in active transport
What do you do if abx peak is too high?
decrease amount of each dose
trough too high?
Which antibiotic's coverage can be described as: Not effective against Staphylococcus or Enterococcus. But effective against GPCs, streptococci, syphilis, Neisseria meningitides (GPR), Clostridium perfringens (GPR), beta-hemolytic Streptococcus, anthrax
Same coverage as penicillin but also picks up enterococci
Name the two abx that are broad-spectrum - pick up GPCs (staph and strep), GNRs, +/- anaerobic coverage. Effective for enterococci but not effective for pseudomonas, acinetobacter or serratia.
Unasyn (ampicillin/sulbactam) and Augmentin (amoxicillin/clavulanic acid)
Name the two antipseudomonal abx that are broad spectrum – pick up GPCs (staph and strep), GNRs, anaerobes. Effective for enterococci; effective for Pseudomonas, Acinetobacter, and Serratia.
Timentin (ticarcillin/clavulanic acid) and Zosyn (piperacillin/sulbactam)
What are the side effects of ticarcillin/piperacillin?
inhibit platelets; high salt load
Name two first generation cephalosporins
Ancef (cefazolin), Keflex (cephalexin)
What does the first generation cephalosporins cover?
GPCs staph and strep
limitations of ancef / keflex
Not effective for enterococcus; does not penetrate CNS
Which first generation cephalosporin is best for phrophylaxis?
cefazolin (Ancef) has the longest half-life
What are the side effects of the first generation cephalosporins?
can produce positive coombs test
Name three 2nd-generation cephalosporins
cefoxitin, cefotetan, cefuroxime
Main side effect of 2nd-generation cephalosporins.