Sedation is a frequent side effect of antipsychotic drugs with a high impact on patients’ functioning. We investigated whether patients who were switched from sedative antipsychotics to sertindole, an antipsychotic drug without sedative effect, showed better results in measures of sleepiness, executive functions and working memory than patients with a good tolerance to sedative effect of olanzapine.

18 patients with schizophrenia treated with sertindole (9 females, mean age 27.9 ± 4,1, mean dose 15.6 ± 3.0 mg/d) and 18 sex and age matched patients treated with olanzapine (15.3 ± 6.5 mg/d) underwent EEG recording, Wisconsin Card Sorting Test (WCST), psychomotor vigilance task, filled out Epworth Sleepiness Scale (ESS) and Athens insomnia scale (AIS). PANSS, UKU, BARS scales and DAI-30 were used to rate mental state, medication side effects and subjective attitude to treatment.

At time of the assessment PANSS scores were similar in sertindole (43.6 ± 7.1) and olanzapine (42.3 ± 12.2) groups. Increased slow wave activity (SWA) was found in EEG in 3 patients treated with sertindole and in 10 with olanzapine (p < 0.05). Treatment with sertindole was also related to lower ratings on BARS scale (p < 0.05) and item “prolongation of sleep” in the UKU scale (p < 0.05). However, no superiority of sertindole was found in other used measures.

Although sertindole does not induce SWA in EEG and prolong sleep, patients who were switched to sertindole did not have improved executive functions, vigilance and working memory as compared to patients treated with olanzapine.