Olanzapine

The aim of this study to assess Rabbit Syndrome (RS) in case of Olanzapine treatment patients with Bipolar affective disorder. Rabbit syndrome (RS) is an antipsychotic-induced rhythmic motion of the mouth/lips resembling the chewing movements of a rabbit. The movement consists of a vertical-only motion, with no involvement of the tongue. Long-term exposure to typical antipsychotics has clearly been associated with RS, but little is known of the risk of RS due to exposure to newer atypical antipsychotics. There have been isolated reports of RS in patients treated with the atypical agents Olanzapine, Risperidone, Aripiprazole and Clozapine. We have observed two cases of Rabbits syndrome in a 45 year old female diagnosed with bipolar affective disorder and 35 year old male patient diagnosed with generalized anxiety and depression treated with Olanzapine.

The present research work was aimed to enhance the solubility and dissolution rate of Olanzapine using Poloxamer as carrier by preparing solid dispersion. The solid dispersions and physical mixtures prepared was also evaluated  for the drug content and percentage drug yield and characterization of prepared systems is done with the help of in-vitro drug release, FTIR, XRD and DSC analysis. The results obtained showed that the percentage yield and percentage drug content was 98.32% and 99% respectively. It was clear that there was no loss of drug and polymer. The rate of dissolution of the drug in the case of solid dispersions was much enhanced as compared to the pure drug and their physical mixtures. FTIR spectra showed that there was not any interaction or hydrogen bonding between the drug and polymers in solid dispersions as well as physical mixtures. The polymorphic changes were studied with the XRD gave the idea that the solid dispersions were quite amorphous in nature as compared to the pure drug. In the diffraction pattern for solid dispersions, the number of crystalline peaks due to drug had disappeared. DSC showed that there was shifting in melting endotherm of drug in case of solid dispersion. From the XRD and DSC it was confirmed that the increase in the solubility and dissolution rate was due to polymorphic transition of drug from crystalline to amorphous form.