Usage
- An ‘older’ but effective anticonvulsant used for the treatment of absence seizures and sometimes absence status epilepticus.
- It is most used in primary generalised epilepsies, particularly childhood absence epilepsy.
- There is now class 1 evidence for efficacy in CAE and it is regarded as the drug of choice.1
Resources
- 1Tracy A. Glauser et al.Ethosuximide, Valproic Acid, and Lamotrigine in Childhood Absence Epilepsy. N Engl J Med 2010; 362:790-799
Side effects
Possible side effects:
The main side effect is GI symptoms (abdominal pain). This is generally 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: AED Prescribing - Pregnancy)
For a complete list of adverse effects, appropriate formularies should be consulted.
Dosing
- The below initiation and escalation doses are only a guide and need to be individualised based on patient (age, weight, co-morbidities), disease (seizure type, frequency, duration) and medication (metabolism, interactions, side-effect profile) characteristics.
- Situations that require more careful consideration include children with higher weights, polytherapy, or multiple co-morbidities. Consultation with appropriate formularies or a paediatric neurologist may be required in specific circumstances.
Commonly used regime
- 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 up to weights of 30-40kgs.
- Maximum dosage in the older adolescent/adult range: 1500mg daily.
Preparations
- 250mg capsule or 50mg/ml syrup forms.
Monitoring
No routine blood tests are necessary.
Interactions | Precautions
- No significant drug interactions occur.
Information last reviewed: 3/05/2023.