Crystapen, Pencillin Sodium Biochemie
|Reviewed by Clinical Practice Committee and Dr Lesley Voss, Natasha Pool and Elizabeth Oliphant|
Add an aminoglycoside if tolerance is suspected/confirmed.
≤29 0 to 28 12 >28 8 30 to 36 0 to 14 12 >14 8 37 to 44 0 to 7 12 >7 8 ≥45 All 6
Benzylpenicillin has bacteriostatic/bacteriocidal actions (depending on its concentration) against most gram positive bacteria and gram negative cocci. Also active against some spirochaetes and actinomycetes. Antimicrobial action is through inhibition of cell wall synthesis.
Well absorbed following intramuscular injection. Widely distributed at varying concentrations in body tissues and fluids. Very little passes into the CSF unless the meninges are inflamed. Larger doses are recommended in meningitis.2 Moderate binding (45-65%) to human plasma protein. Rapidly excreted via the kidney, mainly unchanged. Half life 5-6 hours in healthy newly born preterm infants and 2 hours in full term babies > 1-2 weeks old.
|1||Azimi P.H., Janner D., Berne P. et al. Concentrations of procaine and aqueous penicillin in the cerebrospinal fluid of infants treated for congenital syphilis. J Pediatr 1994;124:649-53.|
|2||American Academy of Pediatrics. Kimberlin D. W, Brady M.T., Jackson M.A., Long S.S. Eds. 2015 Red Book: Report of the Committee on Infectious Diseases. 30th Ed. Elk Grove Village, IL.|
|3||Metsvaht T, Ilmoja ML, Parm U, Maipuu L, Merila M, Lutsar I. Comparison of ampicillin plus gentamicin vs penicillin plus gentamicin in empiric treatment of neonates at risk of early onset sepsis. Acta Paediatr 2010;99:665-72.|
|4||Metsvaht T, Ilmoja ML, Parm U et al. Ampicillin versus penicillin in the empiric therapy of extremely low-birthweight neonates at risk of early onset sepsis. Pediatr Int. 2011 Dec;53(6):873-80.|