Penicillin G

From Anvita Health Wiki

Contents 1 Introduction 2 Dosage 3 Dosage-adjustment-in-renal-failure 4 Pharmacokinetics 5 Antimicrobial-activity 6 Adverse-effects 7 More General Terms 8 Internet Database 9 References

Introduction

• penicillin G. 1st generation penicillin.

Dosage

• Pneumonia: 1-1.5 x 10E5 U/kg/day
• (8-12 x 10E6 U {adults})
• IV divided every 4-6 hours.

• Meningitis: 2.5-3.0 x 10E5 U/kg/day

• (20-30 x 10E6 U {adults})
• IV divided every 4 hours.
• do NOT give intrathecally ( neurotoxic)

• Powder for injection: 1 x 10E6 U, 5 x 10E6 U, 20 x 10E6 U

Dosage-adjustment-in-renal-failure

*  creatinine clearance        dosage* 
*  >  30 mL/min               1-2 x 10E6 units IV every 4 hours 
*  10-30 mL/min#              1-2 x 10E6 units IV every 6 hours 
*   < 10 mL/min               1-2 x 10E6 units IV every 12 hours 
*  post-dialysis                2 x 10E6 units

• * higher doses (3-4 x 10E6 units) should be considered for streptococcal endocarditis or pneumococcal meningitis
• # same dose for continuous arteriovenous hemofiltration

Pharmacokinetics

• distribution

• poor penetration across blood-brain barrier despite inflamed meninges
• crosses placenta
• appears in breast milk

• protein-binding 65%
• metabolized in liver (30%) to penicilloic acid
• time to peak serum concentration: within 1 hour
• elimination 1/2life is 20-50 minutes (6-20 hours ESRD)
• eliminated in the urine
  

• elimination via kidney
• lifetime = 20-50 minutes

Antimicrobial-activity

• Streptococcus species
• Listeria
• Neisseria meningitidis
• Actinomyces
• Clostridium, but not difficile
• Treponema pallidum

Adverse-effects

• uncommon (< 1%)

• thrombophlebitis, convulsions, confusion, drowsiness, fever, rash, electrolyte imbalance, hemolytic anemia, positive direct antiglobulin (Coomb's) test ( DAT), myoclonus, acute interstitial nephritis, Jarisch- Herxheimer reaction, hypersensitivity reactions, anaphylaxis 1:10,000

More General Terms

• penicillin

Internet Database

PubChem: 5905
PubChem: 2349
PubChem: 454662
PubChem: 4729

References

1. The Pharmacological Basis of Therapeutics, 9th ed. Gilman et al, eds. Permagon Press/McGraw Hill, 1996
2. Harrison's Principles of Internal Medicine, 13th ed. Companion Handbook. Isselbacher et al (eds), McGraw-Hill Inc. NY, 1995, pg 161
3. Kaiser Permanente Northern California Regional Drug Formulary, 1998

penicillin G