Olanzapine Pamoate Use for Schizophrenia: Retrospective Records Based Study from a Tertiary Care Hospital

BACKGROUND: Little is known from India about the experience of using olanzapine long-acting antipsychotic injectables (LAI). In this background, this study aimed to evaluate the clinical profile of patients suffering from schizophrenia who were prescribed olanzapine LAI and to evaluate the usefulness and acceptability of olanzapine LAI among these patients. METHODS: In this retrospective study, data of all the patients with schizophrenia receiving olanzapine pamoate, was extracted. RESULTS: 40 patients (males-55%; mean [SD] age- 36.2 (12) years; mean duration of illness (SD) prior to depot-143.3 (115.9) months) were included in the study. Olanzapine LAI was invariably prescribed in patients with a past history of non-compliance. Data was available for a mean (SD) follow-up duration of 17 (10.8) months. The most frequently used dose of olanzapine LAI used was 300 mg every two weeks (55%). This was followed by 405 mg every four weeks in (32.5%). Mean Clinical Global Impression (CGI) Severity score prior to starting of olanzapine LAI was 5.8 (0.7), which reduced to 2.7 (1.1) at the time of last follow-up or the last use of olanzapine LAI, and this was a statistically significant improvement (paired t-test value = 16.41; P < 0.001). Only one (2.5%) patient experienced Post injection Delirium/Sedation Syndrome during the study period. Only one patient was hospitalized after starting depot olanzapine. CONCLUSION: Olanzapine LAI is mostly used in patients with a history of non-compliance. Olanzapine LAI is associated with a significant reduction in the severity of illness.