akinohanayuki ブログ

学位を持っても、センスのない、感染制御専門薬剤師のブログ.  I have Ph.D. but less sense ID pharmacist.

Penicillins

基本だ Penicillin
 
 
意識高いぞ Penicillin G
 
時には持続だ Penicillin G
 
De-escalation だ PCG, ABPC
 
日本にないぞ Antistaphylococcal penicillins
 
やっぱり基本だ Penicillin
 
UpToDate 

 

Penicillin G is highly active against most Gram-positive cocci, Gram-positive rods, Gram-negative cocci, and anaerobes. Exceptions are bacteria from these classes that have acquired resistance to penicillin as well as certain anaerobes that produce a beta-lactamase such as Bacteroides. Penicillin is only bacteriostatic against enterococci. 


For strains of S. aureus sensitive to oxacillin, antistaphylococcal penicillins are preferable to vancomycin because they are more active in vitro and in clinical studies. 
 
Broad spectrum penicillins have increased activity over penicillin G against Gram-negative bacilli but are variably inactivated by beta-lactamases. 
 
All penicillins have relatively short half-lives and require frequent administration when given parenterally. CSF penetration is poor except in the presence of inflammation. The anti-staphylococcal penicillins need no dose modification when used in the setting of renal failure. 
 
 
Penicillin G is highly active against:
 
  • Gram-positive cocci (except penicillinase-producing staphylococci, penicillin-resistant pneumococci, enterococci, and oxacillin-resistant staphylococci)
  • Gram-positive rods such as Listeria
  • Gram-negative cocci such as Neisseria spp (except penicillinase-producing Neisseria)
  • Most anaerobes (with certain important exceptions, including Bacteroides)
Penicillin G is only bacteriostatic for enterococci; reports document strains with increasing intrinsic resistance to penicillin and, rarely, with high level resistance due to penicillinase production. 
 
Serious infections with enterococci are generally treated with combination therapy of a cell wall active antibiotic such as penicillin, ampicillin, or vancomycin plus gentamicin or streptomycin (unless high level resistance to these aminoglycosides is present). 
 
Penicillin G is not active against gram-negative bacilli because of poor penetration through the porin channel. 
 
Penicillin G  Dosing: Adult
 
Actinomyces species: IV: 
10 to 20 million units/day divided every 4 to 6 hours for 4 to 6 weeks
 
Clostridium species: IV:
Manufacturer’s labeling: 20 million units/day in divided doses every 4 to 6 hours
 
Skin and soft tissue necrotizing infections (off-label use): 
2 to 4 million units every 4 to 6 hours; use in combination with clindamycin and continue until further debridement is not necessary, patient has clinically improved, and patient is afebrile for 48 to 72 hours (IDSA [Stevens 2014])
 
Corynebacterium diphtheriae: IV: 
2 to 3 million units/day in divided doses every 4 to 6 hours for 10 to 12 days
 
Endocarditis, treatment (off-label dose; AHA [Baddour 2015): IV:
 
Enterococcus, native or prosthetic valve (penicillin-susceptible/gentamicin-susceptible strains): 18 to 30 million units/day as continuous infusion or in divided doses every 6 hours with concomitant gentamicin. Duration of therapy: 4 weeks (native valve and symptoms present <3 months); 6 weeks (native valve and symptoms present ≥3 months or prosthetic valve).
 
Enterococcus, native or prosthetic valve (penicillin-susceptible/streptomycin-susceptible/gentamicin-resistant strains): 18 to 30 million units/day as continuous infusion or in divided doses every 6 hours with concomitant streptomycin. Duration of therapy: 4 weeks (native valve and symptoms present <3 months); ≥6 weeks (native valve and symptoms present ≥3 months or prosthetic valve).
 
Viridans group streptococcus (VGS) and S. bovis:
Native valve: Highly penicillin-susceptible (MIC ≤0.12 mcg/mL): 12 to 18 million units/day as continuous infusion or in divided doses every 4 or 6 hours for 4 weeks or 12 to 18 million units/day as continuous infusion or in divided doses every 6 hours for 2 weeks with concomitant gentamicin
 
Native valve: 
Relatively penicillin-resistant (MIC >0.12 to <0.5 mcg/mL): 24 million units/day as continuous infusion or in divided doses every 4 or 6 hours for 4 weeks with concomitant gentamicin for the first 2 weeks
 
Prosthetic valve: 
Highly penicillin-susceptible (MIC ≤0.12 mcg/mL): 24 million units/day as continuous infusion or in divided doses every 4 or 6 hours for 6 weeks (with or without concomitant gentamicin for the first 2 weeks)
 
Prosthetic valve: 
Relatively or fully penicillin-resistant (MIC >0.12 mcg/mL): 24 million units/day as continuous infusion or in divided doses every 4 or 6 hours with concomitant gentamicin for 6 weeks
 
Erysipelas: IV: 
1 to 2 million units every 4 to 6 hours
 
Erysipelothrix: IV: 
2 to 4 million units every 4 hours
 
Fascial space infections: IV: 
2 to 4 million units every 4 to 6 hours with metronidazole
 
Leptospirosis: IV: 
1.5 million units every 6 hours for 7 days
 
Listeria: IV: 
15 to 20 million units/day in divided doses every 4 to 6 hours for 2 weeks (meningitis) or 4 weeks (endocarditis)
 
Lyme disease (meningitis): IV: 
20 million units/day in divided doses
 
Neurosyphilis (including ocular syphilis) (off-label dose): IV: 
18 to 24 million units/day in divided doses every 4 hours (or by continuous infusion) for 10 to 14 days (CDC [Workowski 2015])
 
Prosthetic joint infection: IV:
 
Enterococcus spp (penicillin-susceptible), streptococci (beta-hemolytic): 
20 to 24 million units daily continuous infusion every 24 hours or in divided doses every 4 hours for 4 to 6 weeks (Osmon 2013); Note: For penicillin-susceptible Enterococcus spp, consider addition of aminoglycoside.
 
Propionibacterium acnes: 
20 million units daily continuous infusion every 24 hours or in divided doses every 4 hours for 4 to 6 weeks (Osmon 2013)
 
Streptococcus:
Brain abscess: 
IV: 18 to 24 million units/day in divided doses every 4 hours with metronidazole
 
Endocarditis or osteomyelitis: IV: 
3 to 4 million units every 4 hours for at least 4 weeks
 
Group B streptococcus (neonatal prophylaxis): IV: 5 million units x 1 dose, then 2.5 to 3.0 million units every 4 hours until delivery (CDC 2010)
 
Skin infections, including skin and soft tissue necrotizing infections (off-label use): IV:
 2 to 4 million units every 4 to 6 hours; use in combination with clindamycin for necrotizing infections and continue until further debridement is not necessary, patient has clinically improved, and patient is afebrile for 48 to 72 hours (IDSA [Stevens 2014])
 
Toxic shock: IV: 
24 million units/day in divided doses with clindamycin
 
Streptococcal pneumonia: IV:
 2 to 3 million units every 4 hours
 
Whipple's disease: IV:
 2 million units every 4 hours for 2 weeks, followed by oral trimethoprim/sulfamethoxazole or doxycycline for 1 year
 
Relapse or CNS involvement: 
4 million units every 4 hours for 4 weeks