BNF for Children 2011-2012

BNFC 2011–2012 5.4.6 Trypanocides 3415.4.6 TrypanocidesThe prophylaxis and treatment of trypanosomiasis isdifficult and differs according to the strain of organism.Expert advice should therefore be obtained.5.4.7 Drugs for toxoplasmosisMost infections caused by Toxoplasma gondii are selflimiting,and treatment is not necessary. Exceptions arechildren with eye involvement (toxoplasma choroidoretinitis),and those who are immunosuppressed. Toxoplasmicencephalitis is a common complication ofAIDS. The treatment of choice is a combination ofpyrimethamine and sulfadiazine, given for severalweeks (expert advice essential). Pyrimethamine is afolate antagonist, and adverse reactions to this combinationare relatively common (folinic acid supplements(see p. 418) and weekly blood counts needed). Alternativeregimens use combinations of pyrimethaminewith clindamycin or clarithromycin or azithromycin.Long-term secondary prophylaxis is required after treatmentof toxoplasmosis in immunocompromisedpatients; prophylaxis should continue until immunityrecovers.If toxoplasmosis is acquired in pregnancy, transplacentalinfection may lead to severe disease in the fetus;specialist advice should be sought on management.Spiramycin may reduce the risk of transmission ofmaternal infection to the fetus. When there is evidenceof placental or fetal infection, pyrimethamine may begiven with sulfadiazine and folinic acid after the firsttrimester.In neonates without signs of toxoplasmosis, but born tomothers known to have become infected, spiramycin isgiven while awaiting laboratory results. If toxoplasmosisis confirmed in the infant, pyrimethamine and sulfadiazineare given for 12 months, together with folinic acid.PYRIMETHAMINECautions blood counts required with prolonged treatment;history of seizures—avoid large loading doses;interactions: Appendix 1 (pyrimethamine)Hepatic impairment manufacturer advises cautionRenal impairment manufacturer advises cautionPregnancy theoretical teratogenic risk in first trimester(folate antagonist); adequate folate supplementshould be given to motherBreast-feeding present in milk—avoid breast-feedingduring toxoplasmosis treatment; avoid other folateantagonistsSide-effects depression of haematopoiesis with highdoses, rashes, insomniaLicensed use not licensed for use in children under 5yearsIndication and doseToxoplasmosis in pregnancy (in combinationwith sulfadiazine and folinic acid (section 8.1)),see notes above. By mouthChild 12–18 years 50 mg once daily until deliveryCongenital toxoplasmosis (in combination withsulfadiazine and folinic acid (section 8.1)),. By mouthNeonate 1 mg/kg twice daily for 2 days, then1 mg/kg once daily for 6 months, then 1 mg/kg 3times a week for 6 monthsMalaria no dose stated because not recommendedaloneDaraprim c (GSK) AUTablets, scored, pyrimethamine 25 mg. Net price 30-tab pack = £2.60Extemporaneous formulations available seeExtemporaneous Preparations, p. 6SPIRAMYCINCautions cardiac disease, arrhythmias (including predispositionto QT interval prolongation)Contra-indications sensitivity to other macrolidesHepatic impairment use with cautionBreast-feeding present in breast milkSide-effects gastro-intestinal disturbances includingnausea, vomiting, diarrhoea; dizziness, headache;rash; hepatotoxicity; rarely, prolongation of QTinterval, thrombocytopenia and vasculitisLicensed use not licensedIndication and doseToxoplasmosis in pregnancy see notes above. By mouthChild 12–18 years 1.5 g twice daily until deliveryChemoprophylaxis of congenital toxoplasmosis. By mouthNeonate 50 mg/kg twice dailySpiramycin (Non-proprietary)Tablets, spiramycin 750 000 units (250 mg); 1.5 millionunits (500 mg); 3 million units (1 g)Syrup, spiramycin 75 000 units/mL (25 mg/mL)Note 3000 units : 1 mg spiramycinAvailable from ‘special-order’ manufacturers or specialistimporting companies, see p. 809SULFADIAZINE(Sulphadiazine)Cautions see under Co-trimoxazole, section 5.1.8;interactions: Appendix 1 (sulfonamides)Contra-indications see under Co-trimoxazole, section5.1.8Hepatic impairment use with caution in mild tomoderate impairment; avoid in severe impairmentRenal impairment use with caution in mild to moderateimpairment; avoid in severe impairment; highrisk of crystalluriaPregnancy risk of neonatal haemolysis andmethaemoglobinaemia in third trimester; fear ofincreased risk of kernicterus in neonates appears tobe unfoundedBreast-feeding small risk of kernicterus in jaundicedinfants and of haemolysis in G6PD-deficient infants5 Infections