Olanzapine is a novel antipsychotic agent. It has a pleotrophic pharmacology and affects dopaminergic, serotonergic, muscarinic and adrenergic activities. The therapeutic advantage of recent antipsychotics (so-called atypical antipsychotics) has been attributed to alpha-2 adrenergic antagonist effects.

The aim of this study was to evaluated effectiveness of Olanzapine in patients with schizophrenia.

Study was designed for 8-week, observational study. 40 patients, both genders, aged 20-65 years, with diagnosed various types of schizophrenia were enrolled in the study as outpatient and inpatient setting. The patients had to have a total score ≥40 on Positive and Negative scale - two parts of the Positive and Negative Syndrome Scale (PANSS). The efficacy parameter was the percent of score difference between baseline and week 8 of therapy on two above-mentioned PANSS subscales. The difference was considered as significant improvement if decrease from the baseline was 20% or more.

All 40 enrolled patients completed the study. After the 8 weeks of treatment, 32/40 patients (80%) had clinically significant improvement of 20% or more decreased total PANSS score (Positive and Negative subscale). In 8/40 patients (20%) clinical improvement was also reported with < 20% decreased total PANSS score.

In this observational study olanzapine appears to be very good effectiveness in patients with schizophrenia.