BNF for Children 2011-2012

258 5.1.1 Penicillins BNFC 2011–20125 InfectionsPhenoxymethylpenicillin (Penicillin V) has a similarantibacterial spectrum to benzylpenicillin, but is lessactive. It is gastric acid-stable, so is suitable for oraladministration. It should not be used for serious infectionsbecause absorption can be unpredictable andplasma concentrations variable. It is indicated principallyfor respiratory-tract infections in children, forstreptococcal tonsillitis, and for continuing treatmentafter one or more injections of benzylpenicillin whenclinical response has begun. It should not be used formeningococcal or gonococcal infections. Phenoxymethylpenicillinis used for prophylaxis against streptococcalinfections following rheumatic fever and againstpneumococcal infections following splenectomy or insickle cell disease.Oral infections Phenoxymethylpenicillin is effectivefor dentoalveolar abscess.BENZYLPENICILLIN SODIUM(Penicillin G)Cautions history of allergy; false-positive urinary glucose(if tested for reducing substances); interactions:Appendix 1 (penicillins)Contra-indications penicillin hypersensitivityRenal impairment neurotoxicity—high doses maycause convulsions. Estimated glomerular filtrationrate 10–50 mL/minute/1.73 m 2 , use normal doseevery 8–12 hours; estimated glomerular filtration rateless than 10 mL/minute/1.73 m 2 use normal doseevery 12 hoursPregnancy not known to be harmfulBreast-feeding trace amounts in milk—not known tobe harmful, but be alert for hypersensitivity in infantSide-effects hypersensitivity reactions including urticaria,fever, joint pains, rashes, angioedema, anaphylaxis,serum sickness-like reactions; rarely CNS toxicityincluding convulsions (especially with high dosesor in severe renal impairment), interstitial nephritis,haemolytic anaemia, leucopenia, thrombocytopeniaand coagulation disorders; also reported diarrhoea(including antibiotic-associated colitis)Indication and doseMild to moderate susceptible infections(including throat infections, otitis media,pneumonia, cellulitis, neonatal sepsis, Table 1,section 5.1). By intramuscular injection or by slow intravenousinjection or infusion (intravenous routerecommended in neonates and infants)Neonate under 7 days 25 mg/kg every 12 hours;dose doubled in severe infectionNeonate 7–28 days 25 mg/kg every 8 hours;dose doubled in severe infectionChild 1 month–18 years 25 mg/kg every 6 hours;increased to 50 mg/kg every 4–6 hours (max. 2.4 gevery 4 hours) in severe infectionEndocarditis (combined with another antibacterialif necessary, see Table 1, section 5.1). By slow intravenous injection or infusionChild 1 month–18 years 25 mg/kg every 4 hours,increased if necessary to 50 mg/kg (max. 2.4 g)every 4 hoursMeningitis, meningococcal disease. By slow intravenous injection or infusionNeonate 75 mg/kg every 8 hoursChild 1 month–18 years 50 mg/kg every 4–6hours (max. 2.4 g every 4 hours)Important. If meningococcal disease (meningitis withnon-blanching rash or meningococcal septicaemia) issuspected, a single dose of benzylpenicillin should begiven before transferring the child to hospital urgently, solong as this does not delay the transfer. If a child withsuspected bacterial meningitis without non-blanchingrash cannot be transferred to hospital urgently, a singledose of benzylpenicillin should be given before the transfer.Suitable doses of benzylpenicillin by intravenousinjection (or by intramuscular injection) are: Infantunder 1 year 300 mg; Child 1–9 years 600 mg, 10 yearsand over 1.2 g. In penicillin allergy, cefotaxime (section5.1.2) may be an alternative; chloramphenicol (section5.1.7) may be used if there is a history of anaphylaxis topenicillinsProven or suspected neonatal group B streptococcusinfection. By slow intravenous injection or infusionNeonate under 7 days 50 mg/kg every 12 hoursNeonate 7–28 days 50 mg/kg every 8 hoursProphylaxis in limb amputation Table 2, section5.1Administration Intravenous route recommended inneonates and infants. For intravenous infusion, dilutewith Glucose 5% or Sodium Chloride 0.9%; give over15–30 minutes. Longer administration time is particularlyimportant when using doses of 50 mg/kg (orgreater) to avoid CNS toxicitySafe practiceIntrathecal injection of benzylpenicillin is not recommendedCrystapen c (Genus) AInjection, powder for reconstitution, benzylpenicillinsodium (unbuffered), net price 600-mg vial = 95p, 2-vial ‘GP pack’ = £2.64; 1.2-g vial = £1.89Electrolytes Na + 1.68 mmol/600-mg vial; 3.36 mmol/1.2-g vialPHENOXYMETHYLPENICILLIN(Penicillin V)Cautions see under Benzylpenicillin; interactions:Appendix 1 (penicillins)Contra-indications see under BenzylpenicillinPregnancy not known to be harmfulBreast-feeding trace amounts in milk—not known tobe harmful, but be alert for hypersensitivity in infantSide-effects see under BenzylpenicillinIndication and doseSusceptible infections including oral infections,tonsillitis, otitis media, erysipelas,cellulitis. By mouthChild 1 month–1 year 62.5 mg 4 times daily;increased up to 12.5 mg/kg 4 times daily in severeinfectionChild 1–6 years 125 mg 4 times daily; increasedup to 12.5 mg/kg 4 times daily in severe infection