Children's epilepsy resource for Clinicians

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  • An ‘older’ but effective anticonvulsant.  It is most used in primary generalised epilepsies, particularly CAE. 
  • There is now class 1 evidence for efficacy in CAE and it is regarded as the drug of choice. [1]


NOTABLE Side Effects:

  • The main side effect is GI symptoms (abdominal pain).  This generally is dose-dependent but can be intolerable and necessitate stopping the drug.
  • Hiccups
  • Rash
  • Joint pain
  • Drowsiness or lethargy
  • All anticonvulsants are potentially teratogenic and this is often dose related (see section: Pregnancy and AEDs)
  • For a complete list of adverse effects, appropriate formularies should be consulted.



  • The initiation and escalation dose depends upon age, weight, syndrome, seizure frequency and severity, and side effect profile.
  • Unfortunately, one dose regime does not fit all. A Paediatric Neurologist should be consulted if there is uncertainty.


A commonly used regime is below:

  • Start 10-15mg/kg/day in two divided doses increasing weekly. 
  • Around 20mg/kg/day is a reasonable target dose.  Higher doses above 30mg/kg/day may be effective but GI symptoms are more frequent.
  • Dosages per kilogram can only be used in children of weight approximately up to 30-40kgs. Consult appropriate formularies for higher weights and in the adult range.
  • These dosages are only a guideline and appropriate formularies should be consulted as needed. 



  • 250mg capsule or 50mg/ml syrup forms.


Monitoring and Levels:

  • No routine blood tests are necessary. 


Drug Interactions

  • No significant drug interactions occur.







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This website was created in March 2012. This page was last modified in December 2017. 


[1] Tracy A. Glauser et al.Ethosuximide, Valproic Acid, and Lamotrigine in Childhood Absence Epilepsy. N Engl J Med 2010; 362:790-799