BNF for Children 2011-2012

BNFC 2011–2012 9.8.1 Drugs used in metabolic disorders 489Side-effects initially nausea, anorexia, fever, and skinreactions; taste loss (mineral supplements notrecommended); blood disorders including thrombocytopenia,leucopenia, agranulocytosis and aplasticanaemia; proteinuria, rarely haematuria (withdrawimmediately and seek specialist advice); haemolyticanaemia, pancreatitis, cholestatic jaundice, nephroticsyndrome, lupus erythematosus-like syndrome,myasthenia gravis-like syndrome, neuropathy (especiallyif neurological involvement in Wilson’s disease—prophylacticpyridoxine recommended, seesection 9.6.2, polymyositis (rarely with cardiac involvement),dermatomyositis, mouth ulcers, stomatitis,alopecia, bronchiolitis and pneumonitis, pemphigus,Goodpasture’s syndrome, and Stevens-Johnsonsyndrome also reported; male and female breastenlargement reported; in non-rheumatoid conditionsrheumatoid arthritis-like syndrome also reported; laterashes (consider withdrawing treatment)Indication and doseWilson’s disease. By mouthChild 1 month–12 years 2.5 mg/kg twice dailybefore food, increased at 1–2 week intervals to10 mg/kg twice dailyChild 12–18 years 0.75–1 g twice daily beforefood, max. 2 g daily for 1 year; usual maintenancedose 0.75–1 g dailyCystinuria. By mouthChild 1 month–12 years 5–10 mg/kg twice dailybefore food, adjusted to maintain urinary cystinebelow 200 mg/litre; maintain adequate fluid intakeChild 12–18 years 0.5–1.5 g twice daily beforefood, adjusted to maintain urinary cystine below200 mg/litre; maintain adequate fluid intakePenicillamine (Non-proprietary) ATablets, penicillamine 125 mg, net price 56-tab pack= £16.66; 250 mg, 56-tab pack = £25.00. Label: 6, 22,counselling, blood disorder symptoms (see above)Distamine c (Alliance) ATablets, all f/c, penicillamine 125 mg, net price 100 =£10.34; 250 mg, 100 = £17.78. Label: 6, 22, counselling,blood disorder symptoms (see above)TRIENTINE DIHYDROCHLORIDECautions see notes above; interactions: Appendix 1(trientine)Pregnancy teratogenic in animal studies—use only ifbenefit outweighs risk; monitor maternal and neonatalserum-copper concentrationsSide-effects nausea, rash; very rarely anaemia; duodenitisand colitis also reportedIndication and doseWilson’s disease in patients intolerant ofpenicillamine. By mouthChild 2–12 years 0.6–1.5 g daily in 2–4 divideddoses before food, adjusted according to response;reduce dose and increase frequency if nausea is aproblemChild 12–18 years 1.2–2.4 g daily in 2–4 divideddoses before food, adjusted according to response;reduce dose and increase frequency if nausea is aproblemTrientine Dihydrochloride (Univar) ACapsules, trientine dihydrochloride 300 mg. Label: 6,22ZINC ACETATECautions portal hypertension (risk of hepatic decompensationwhen switching from chelating agent);monitor full blood count and serum cholesterol;interactions: Appendix 1 (zinc)Pregnancy usual dose 25 mg 3 times daily adjustedaccording to plasma-copper concentration andurinary copper excretionBreast-feeding manufacturer advises avoid; presentin milk—may cause zinc-induced copper deficiency ininfantSide-effects gastric irritation (usually transient; maybe reduced if first dose taken mid-morning or with alittle protein); less commonly sideroblastic anaemiaand leucopeniaIndication and doseWilson’s diseaseNote dose expressed as elemental zinc. By mouthChild 1–6 years 25 mg twice dailyChild 6–16 years body-weight under 57 kg, 25 mg3 times daily; body-weight 57 kg or over, 50 mg 3times dailyChild 16–18 years 50 mg 3 times dailyWilzin c (Orphan Europe) ACapsules, zinc (as acetate) 25 mg (blue), net price250-cap pack = £132.00; 50 mg (orange), 250-cappack = £242.00. Label: 23Administration capsules may be opened and the contents mixedwith waterCarnitine deficiencyCarnitine is available for the management of primarycarnitine deficiency due to inborn errors of metabolism,or of secondary deficiency in haemodialysis patients.Carnitine is also used in the treatment of some organicacidaemias; however, use in fatty acid oxidation iscontroversial.CARNITINECautions diabetes mellitus; monitoring of free andacyl carnitine in blood and urine recommendedRenal impairment accumulation of metabolites mayoccur with chronic oral administration in severeimpairmentPregnancy appropriate to use; no evidence of teratogenicityin animal studiesSide-effects nausea, vomiting, abdominal pain, diarrhoea,fishy body odour; side-effects may be doserelated—monitortolerance during first week and afterany dose increase9 Nutrition and blood