BNF for Children 2011-2012

BNFC 2011–2012 9.8.2 Acute porphyrias 497Indication and doseHereditary tyrosinaemia type I (in combinationwith dietary restriction of tyrosine and phenylalanine). By mouthNeonate initially 500 micrograms/kg twice daily,adjusted according to response; max. 2 mg/kgdailyChild 1 month–18 years initially 500 micrograms/kgtwice daily, adjusted according toresponse; max. 2 mg/kg dailyAdministration capsules can be opened and the contentssuspended in a small amount of water or formuladiet and taken immediatelyOrfadin c (Swedish Orphan) ACapsules, nitisinone 2 mg, net price 60-cap pack =£564.00; 5 mg, 60-cap pack = £1127.00; 10 mg, 60-cappack = £2062.00SODIUM DICHLOROACETATEPregnancy no information availableBreast-feeding no information availableSide-effects polyneuropathy on prolonged use;abnormal oxalate metabolism; metabolic acidosisIndication and dosePyruvate dehydrogenase defects. By mouthNeonate initially 12.5 mg/kg 4 times daily,adjusted according to response; up to 200 mg/kgdaily may be requiredChild 1 month–18 years initially 12.5 mg/kg 4times daily, adjusted according to response; up to200 mg/kg daily may be requiredSodium dichloroacetate (Non-proprietary) APowder (for oral solution), sodium dichloroacetate50 mg/mL when reconstituted with waterAvailable from ‘special-order’ manufacturers or specialistimporting companies, see p. 809UBIDECARENONE(Ubiquinone, Co-enzyme Q10)Cautions may reduce insulin requirement in diabetesmellitus; interactions: Appendix 1 (ubidecarenone)Hepatic impairment reduce dose in moderate andsevere impairmentSide-effects nausea, diarrhoea, heartburn; rarelyheadache, irritability, agitation, dizzinessLicensed use not licensedIndication and doseMitochondrial disorders. By mouthNeonate initially 5 mg once or twice daily withfood, adjusted according to response, up to 200 mgdaily may be requiredChild 1 month–18 years initially 5 mg once ortwice daily with food, adjusted according toresponse, up to 300 mg daily may be requiredUbidecarenone (Non-proprietary) AOral solution, ubidecarenone 50 mg/10 mLTablets, ubidecarenone 10 mgCapsules, ubidecarenone 10 mg, 30 mgAvailable from ‘special-order’ manufacturers or specialistimporting companies, see p. 8099.8.2 Acute porphyriasThe acute porphyrias (acute intermittent porphyria,variegate porphyria, hereditary coproporphyria, and 5-aminolaevulinic acid dehydratase deficiency porphyria)are hereditary disorders of haem biosynthesis; they havea prevalence of about 1 in 10 000 of the population.Great care must be taken when prescribing for patientswith acute porphyria, since certain drugs can induceacute porphyric crises. Since acute porphyrias arehereditary, relatives of affected individuals should bescreened and advised about the potential danger ofcertain drugs. Acute attacks of porphyria are exceptionallyrare before puberty. When acute porphyria is suspectedin a child, support from an expert porphyriaservice should be sought.Treatment of serious or life-threatening conditionsshould not be withheld from patients with acute porphyria.When there is no safe alternative, treatmentshould be started and urinary porphobilinogen excretionshould be measured regularly; if it increases orsymptoms occur, the drug can be withdrawn and theacute attack treated. If an acute attack of porphyriaoccurs during pregnancy, contact an expert porphyriaservice for further advice.Haem arginate is administered by short intravenousinfusion as haem replacement in moderate, severe, orunremitting acute porphyria crises.Supplies of haem arginate may be obtained in an emergencyoutside office hours from the on-call pharmacistat:St Thomas’ HospitalLondonTel: (020) 7188 7188HAEM ARGINATE(Human hemin)Pregnancy manufacturer advises avoid unless essentialBreast-feeding manufacturer advises avoid unlessessential—no information availableSide-effects rarely hypersensitivity reactions andfever; pain and thrombophlebitis at injection siteIndication and doseAcute porphyrias (acute intermittent porphyria,porphyria variegata, hereditary coproporphyria). By intravenous infusionChild 1 month–18 years 3 mg/kg once daily(max. 250 mg daily) for 4 days; if response inadequate,repeat 4-day course with close biochemicalmonitoringNormosang c (Orphan Europe) TAConcentrate for intravenous infusion, haem arginate25 mg/mL, net price 10-mL amp = £434.25Administration administer over at least 30 minutes; diluterequisite dose in 100 mL Sodium Chloride 0.9% in glass bottle;administer within 1 hour after dilution; max. concentration2.5 mg/mL9 Nutrition and blood