chapter 5

• penicillins (narrow spectrum: penase-susceptible, penicillin G, penicillin V)

  • activity spectrum & clinical use - streptococcal and meningcoccal infections - syphilis
  • pharmacokinetics and interactions - rapid renal elimination; short half lives necessitate frequent dosing, some biliary clearance of nafcillin and oxacillin
  • toxicities - hypersensitivity reaction (5-6% incidence), assume complete cross-reactivity; GI distress and maculopapular rash (ampicillin)
• penicillins (narrow spectrum: penase-resistant, nafcillin, oxacillin)

  • activity spectrum & clinical use - staphylococcal infections
  • pharmacokinetics and interactions - rapid renal elimination; short half lives necessitate frequent dosing, some biliary clearance of nafcillin and oxacillin
  • toxicities - hypersensitivity reaction (5-6% incidence), assume complete cross-reactivity; GI distress and maculopapular rash (ampicillin)
• penicillins (wider spectrum, penicillinase inhibitor: ampicillin, amoxicillin, piperacillin, ticarcilllin)

  • activity spectrum & clinical use - all penicillins and cephalosporins are bactericidal
  • pharmacokinetics and interactions - rapid renal elimination; short half lives necessitate frequent dosing, some biliary clearance of nafcillin and oxacillin
  • toxicities - hypersensitivity reaction (5-6% incidence), assume complete cross-reactivity; GI distress and maculopapular rash (ampicillin)
• cephalosporins (first gen- cephalexin, others)

  • activity spectrum & clinical use - skin, soft tissue UT infections
  • pharmacokinetics and interactions - oral use for older drugs, iv for newer - renal elimination. short half lives, third generation enter CNS
  • toxicities - hypersensitivity reaction (2% incidence), assume complete cross-reactivity; partial with penicillins; GI distress
• cephalosporins (second gen- cefotetan, cefoxitin, cefuroxime)

  • activity spectrum & clinical use - more active vs S. pneumoniae and H influenzae; b fragilis (cefotetan)
  • pharmacokinetics and interactions - oral use for older drugs, iv for newer - renal elimination. short half lives, third generation enter CNS
  • toxicities - hypersensitivity reaction (2% incidence), assume complete cross-reactivity; partial with penicillins; GI distress
• cephalosporins (fourth gen- cefepime)

  • activity spectrum & clinical use - broad activity, beta lactamase stable
  • pharmacokinetics and interactions - oral use for older drugs, iv for newer - renal elimination. short half lives, third generation enter CNS
  • toxicities - hypersensitivity reaction (2% incidence), assume complete cross-reactivity; partial with penicillins; GI distress
• carbapenems (imipenem-cilastatin, doripenem, meropenem, ertapenem)

  • activity spectrum & clinical use - broad spectrume includes some PRSP strains, gram negative rods, and pseudomonas sp
  • pharmacokinetics and interactions - parenteral; cilastin inhibits renal metabolism of imipenem; renal elimination
  • toxicities - partial cross-reactivity with penicillins; CNS effects include confusion and seizures
• monobactams (aztreonam)

  • activity spectrum & clinical use - active only vs gram-negative bacteria; klebsiella, pseudomonas, and serratia spp
  • pharmacokinetics and interactions - parenteral; renal elimination
  • toxicities - GI upsets, headache, vertigo; no cross allergenicity with beta lactams
• glycopeptides (vancomycin )

  • activity spectrum & clinical use -gram posi activity includes MRSA and PRSP strains
  • pharmacokinetics and interactions - parenteral; oral for C difficile colitis; renal elimination IV only long half life
  • toxicities - red man syndrome, rare nephrotoxicity
• glycopeptides (teicoplanin )

  • activity spectrum & clinical use -teicoplanin as for vancomycin
  • pharmacokinetics and interactions - parenteral; oral for C difficile colitis; renal elimination IV only long half life
  • toxicities - red man syndrome, rare nephrotoxicity
• lipopeptide (daptomycin )

  • activity spectrum & clinical use -gram posi activity used in endocarditis and sepsis
  • pharmacokinetics and interactions - renal elimination
  • toxicities - myopathy, monitor CPK weekly