EFFICACY OF LEVETIRACETAM IN STIMULUS-SENSITIVE (REFLEX) EPILEPSY

Objectives: Levetiracetam (LEV) is a novel anti-epileptic drug with efficacy against stimulus-sensitive epilepsy in animal models. It has been reported to be effective in the treatment of photosensitive epilepsy. These findings prompted a trial of levetiracetam in patients with stimulus-sensitive (reflex) epilepsy.

Methods: Six patients, ranging from 3–18 years, were evaluated for stimulus-sensitive seizures. Clinical seizures were provoked by auditory stimuli in one patient, tactile stimuli in four patients, and photic stimulation in one patient. In two patients with acute symptomatic seizures, ictal epileptic activity was confirmed during continuous EEG monitoring. In the other four patients with remote symptomatic CNS injury, interictal epileptiform abnormalities were noted on EEG, and clinical seizures consistent with previously reported features, were provoked following patient-specific stimuli. These seizures interfered with caregiving and nursing tasks, as well as activities of daily living.

Results: Following the initiation of LEV, at doses ranging from 20–60mg/kg/day, all patients showed a marked and sustained response to therapy (minimal or no seizure activity following stimuli). Two patients with acute symptomatic seizures were weaned off LEV in a few weeks, without recurrence of seizures. Four patients with remote symptomatic seizures, remain on LEV with significant attenuation of seizure severity in occasional break-through seizures. Reduction of provoked seizures resulted in improved quality of care in acutely ill patients; caregivers and school personnel reported improvement in activities of daily living in the other patients. Conclusion: LEV has a rapid, marked and sustained clinical response effective in stimulus-sensitive (reflex) seizures. Clinical efficacy is noted in patients with acute as well as remote symptomatic etiology of reflex seizures, and is associated with increased ease of care-giving and improvement of social functioning.