Rufinamide

Usage

  • Rufinamide is primarily used as adjunctive treatment for drug resistant seizures in Lennox-Gastaut syndrome, particularly for drop attacks.
  • It has also been used in other drug-resistant epilepsies, for example: myoclonic astatic epilepsy, structural and genetic related epilepsies.

Rufinamide

Side effects

Common side effects

  • Sleepiness
  • Vomiting
  • Headache
  • Dizziness
  • Fatigue
  • Nausea
  • Constipation
  • Diarrhoea
  • Blurred vision

Other notable side effects

  • Less commonly: weight loss, insomnia, anxiety
  • Rarely: hypersensitivity reaction (fever, rash, lymphadenopathy, haematuria, deranged liver function tests)
  • 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 initiation and escalation dose depends upon age, weight, syndrome, seizure frequency and severity, and side effect profile.

Effective and safe doses vary. Unfortunately, a one dose regime does not fit all. A Paediatric Neurologist should be consulted if there is uncertainty.

Commonly used regime

  • Initial dose: 10mg/kg/day given in 2 divided doses
  • For escalation dosage, titration of 5-10 mg/kg/day per week or fortnight is reasonable to minimise side-effects.
  • A recommended maintenance dose is 20-45 mg/kg/day
  • 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.
 
Preparations

  • Tablets: 200mg and 400mg tablets. These may be crushed and given with water.
  • Oral suspension: 40mg/mL

Interactions | Precautions

    Contraindications

    • SCN1A associated disorders.
    • Rufinamide can cause decrease of the QT interval. An ECG before starting treatment may be necessary and it should not be given to patients with a history of congenital short QT interval.

    Precautions

    • Co-administration with Sodium Valproate decreases the clearance of Rufinamide therefore lower dosage of Rufinamide is recommended.
    • Conversely, co-administration with enzyme inducing drugs will tend to reduce plasma levels of Rufinamide and a higher dose of Rufinamide may be required.
    • Rufinamide has been associated with a drug hypersensitivity reaction and Stevens-Johnson syndrome. The majority of reported cases have occurred in children <12 years age and within the first 4 weeks of starting Rufinamide therapy.
    • Rufinamide enhances metabolism of oral contraceptives and potentially reduces their effectiveness.

    Weaning

    • Gradual reduction (over a minimum of a week) minimises the risk of increased seizure frequency or status epilepticus in patients with seizure disorders.

    Pregnancy

    • All anticonvulsants are potentially teratogenic and this is often dose related (see section: AED Prescribing - Pregnancy)
    • There is limited data on the safety of Rufinamide in pregnancy.
    • Usage in pregnancy needs to be discussed with a neurologist