Objective and Subjective Assessment of the Effect of Levetiracetam on Daytime Sleepiness in Patients with Epilepsy

Levetiracetam (LEV) is a newer generation antiepileptic drug with unique anticonvulsive mechanism of action. It has been reported to cause daytime sleepiness in 4–15% of patients with epilepsy.

We studied the effect of 2000 mg LEV monotherapy on daytime sleepiness over a 3-month period in patients with epilepsy. The subjective assessment of daytime sleepiness was made through Epworth sleepiness scale (ESS), and the objective assessment—through four naps MSLT. Both procedures were performed at baseline and after a 3-month period of LEV treatment. The dynamics in ESS score was measured as a shift from normal to excessive daytime sleepiness or vice versa. We studied two MSLT variables—mean sleep latency for all four naps and sleep stage. The dynamics in the mean sleep latency from baseline to the end of the third month of LEV treatment was also measured.

Twenty five patients participated in our study. The subjective and objective assessment of daytime sleepiness matched in only five of them. In none of the patients, ESS score was worsened after therapy. There was no statistically significant difference between the subjective assessment at baseline and after therapy (p = 0.250). There was no statistically significant difference between the objective assessment of daytime sleepiness at baseline and after therapy (r = 0.13). The patients with prolonged mean sleep latency reached a deeper sleep stage after therapy. The daytime sleepiness assessment correlated only with seizure frequency—patients with > 1 seizure a year had less variation in the degree of daytime sleepiness, i.e. more constant mean sleep latency.

LEV 2000 mg/day does not worsen the subjective and the objective assessment of daytime sleepiness in patients with newly diagnosed or untreated epilepsy.