BNF for Children 2011-2012

BNFC 2011–2012 4.8.3 Febrile convulsions 235Other forms of epilepsy section 4.8.1Note For therapeutic purposes phenobarbital and phenobarbitalsodium may be considered equivalent in effectAdministration for intravenous injection, dilute to aconcentration of 20 mg/mL with Water for InjectionsPhenobarbital (Non-proprietary) 3Injection, phenobarbital sodium 15 mg/mL, net price1-mL amp = £1.64; 30 mg/mL, 1-mL amp = £2.04;60 mg/mL, 1-mL amp = £2.14; 200 mg/mL, 1-mLamp = £2.00Excipients include propylene glycol (see Excipients, p. 2)Note Must be diluted before intravenous administration (seeAdministration)Oral preparationsSection 4.8.1PHENYTOIN SODIUMCautions see notes above; respiratory depression;hypotension and heart failure; resuscitation facilitiesmust be available; injection solutions alkaline (irritantto tissues); see also p. 224; interactions: see p. 215and Appendix 1 (phenytoin)Contra-indications sinus bradycardia, sino-atrialblock, and second- and third-degree heart block;Stokes-Adams syndrome; acute porphyria (section9.8.2)Hepatic impairment see Phenytoin, section 4.8.1Pregnancy see Phenytoin, section 4.8.1 andPregnancy, p. 216Breast-feeding see Phenytoin, section 4.8.1Side-effects intravenous injection may cause cardiovascularand CNS depression (particularly if injectiontoo rapid) with arrhythmias, hypotension, and cardiovascularcollapse; alterations in respiratory function(including respiratory arrest); also reported tonicseizures, purple glove syndrome; see also p. 224Indication and doseStatus epilepticus, acute symptomatic seizuresassociated with trauma or neurosurgery. By slow intravenous injection or infusion (withblood-pressure and ECG monitoring)Neonate initially 20 mg/kg as a loading dose then2.5–5 mg/kg twice dailyChild 1 month–12 years initially 20 mg/kg as aloading dose then 2.5–5 mg/kg twice dailyChild 12–18 years initially 20 mg/kg as a loadingdose then up to 100 mg 3–4 times dailyOther forms of epilepsy section 4.8.1Note Phenytoin sodium doses in BNFC may differ fromthose in product literatureAdministration before and after administration flushintravenous line with Sodium Chloride 0.9%.For intravenous injection, give into a large vein at ratenot exceeding 1 mg/kg/minute (max. 50 mg/minute).For intravenous infusion, dilute to a concentration notexceeding 10 mg/mL with Sodium Chloride 0.9% andgive into a large vein through an in-line filter (0.22–0.50 micron) at a rate not exceeding 1 mg/kg/minute(max. 50 mg/minute); complete administration within1 hour of preparationPhenytoin (Non-proprietary) AInjection, phenytoin sodium 50 mg/mL with propyleneglycol 40% and alcohol 10% in water for injections,net price 5-mL amp = £3.40Epanutin c Ready-Mixed Parenteral (Pfizer) AInjection, phenytoin sodium 50 mg/mL with propyleneglycol 40% and alcohol 10% in water for injections.Net price 5-mL amp = £4.88Oral preparationsSection 4.8.14.8.3 Febrile convulsionsBrief febrile convulsions need no specific treatment;antipyretic medication (e.g. paracetamol, section4.7.1) is commonly used to reduce fever and preventfurther convulsions but evidence to support this practiceis lacking. Prolonged febrile convulsions (those lasting 5minutes or longer), or recurrent febrile convulsionswithout recovery, must be treated actively (as for convulsivestatus epilepticus section 4.8.2).Long-term anticonvulsant prophylaxis for febrile convulsionsis rarely indicated.4.9 Drugs used in dystoniasand related disorders4.9.1 Dopaminergic drugs used in dystonias4.9.2 Antimuscarinic drugs used indystonias4.9.3 Drugs used in essential tremor,chorea, tics, and related disordersDystonias may result from conditions such as cerebralpalsy or may be related to a deficiency of the neurotransmitterdopamine as in Segawa syndrome.4.9.1 Dopaminergic drugs usedin dystoniasLevodopa, the amino-acid precursor of dopamine, actsby replenishing depleted striatal dopamine. It is givenwith an extracerebral dopa-decarboxylase inhibitor,which reduces the peripheral conversion of levodopato dopamine, thereby limiting side-effects such asnausea, vomiting, and cardiovascular effects; additionally,effective brain-dopamine concentrations can beachieved with lower doses of levodopa. The extracerebraldopa-decarboxylase inhibitor most commonlyused in children is carbidopa (in co-careldopa).Levodopa therapy should be initiated at a low dose andincreased in small steps; the final dose should be as lowas possible. Intervals between doses should be chosento suit the needs of the individual child.In severe dystonias related to cerebral palsy, improvementcan be expected within 2 weeks. Children withSegawa syndrome are particularly sensitive to levodopa;they may even become symptom free on small doses.Levodopa also has a role in treating metabolic disorderssuch as defects in tetrahydrobiopterin synthesis and4 Central nervous system