De novo convulsive status epilepticus in patients with multiple sclerosis treated with dalfampridine.

BACKGROUND

Dalfampridine extended release (DAL) is a broad-spectrum voltage-gated potassium channel blocker that is indicated in multiple sclerosis to improve the nerve conduction of demyelinated axons. Seizures are a known side effect of DAL, which is contraindicated in patients with a history of epilepsy.

OBJECTIVE

Three cases of multiple sclerosis (MS) with de novo convulsive status epilepticus (CSE) probably related to dalfampridine administration are described.

METHODS

No patients had a history of seizures or renal impairment. Biological tests were normal. A brain magnetic resonance imaging (MRI) showed diffuse cortical and subcortical atrophy without active inflammatory lesions.

RESULTS

All three patients presented with CSE that was attributed to DAL and so was discontinued.

CONCLUSION

These case reports illustrate that, aside from seizures, de novo CSE is a potential complication of MS patients treated with DAL.