Search results for "Olanzapine"
showing 10 items of 32 documents
Enhancement in Phospholipase D Activity as a New Proposed Molecular Mechanism of Haloperidol-Induced Neurotoxicity
2020
Membrane phospholipase D (PLD) is associated with numerous neuronal functions, such as axonal growth, synaptogenesis, formation of secretory vesicles, neurodegeneration, and apoptosis. PLD acts mainly on phosphatidylcholine, from which phosphatidic acid (PA) and choline are formed. In turn, PA is a key element of the PLD-dependent secondary messenger system. Changes in PLD activity are associated with the mechanism of action of olanzapine, an atypical antipsychotic. The aim of the present study was to assess the effect of short-term administration of the first-generation antipsychotic drugs haloperidol, chlorpromazine, and fluphenazine on membrane PLD activity in the rat brain. Animals were…
Solid microcrystalline dispersion films as a new strategy to improve the dissolution rate of poorly water soluble drugs: A case study using olanzapine
2016
In this study, we evaluate the dissolution rate enhancement of solid microcrystalline dispersion (SMD) films of olanzapine (OLZ) formulated with four water-soluble polymers namely poly(N-vinylpyrrolidone) (PVP), poloxamer 188 (P188), poloxamer 407 (P407) and Soluplus(®) (SLP). Prepared formulations were characterised to determine particle size, morphology, hydrogen bonding interactions, thermal characteristics as well as in vitro dissolution studies conducted under sink conditions (pH 6.8). Particle size of OLZ in all formulations ranged between 42 and 58μm. Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR), Differential Scanning Calorimetry (DSC) and Hot-Stage…
Subchronic Effects of Olanzapine on Sleep EEG in Schizophrenic Patients with Predominantly Negative Symptoms
2004
Background It is well known that sleep disturbance is an integral symptom of schizophrenia. In recent studies, a deficit of delta sleep has been observed in schizophrenic patients. Antipsychotic drugs with serotonin (5-HT2) receptor-antagonistic properties are considered to have delta sleep promoting effects. We have investigated the effects of subchronic olanzapine treatment on sleep EEG in schizophrenic patients. Methods The effects of administration of olanzapine (15 to 20 mg) on sleep were studied for four weeks in 10 male, drug-free patients suffering from schizophrenia with predominantly negative symptoms. Conventional sleep EEG parameters were investigated at baseline and after treat…
Predictors of clinical remission following a first episode of non-affective psychosis: Sociodemographics, premorbid and clinical variables
2012
The aim of the study was to identify predictors associated with a lower likelihood of achieving a clinical remission 1 year after the first break of the illness. Participants were 174 consecutive subjects included in a first episode programme with no prior treatment with antipsychotic medication. Patients were assigned to haloperidol, olanzapine or risperidone in a randomized, open-label, prospective clinical trial. The main outcome variable was the remission criteria developed by the Remission in Schizophrenia Working Group. Clinical variables were included in a logistic regression analysis in order to predict the remission state at 1 year. At 1 year, 31% of patients met criteria for remis…
Dopamine D2 Receptor Occupancy Estimated From Plasma Concentrations of Four Different Antipsychotics and the Subjective Experience of Physical and Me…
2019
Background Impaired subjective well-being in schizophrenia patients treated with antipsychotics has often been linked inter alia to the antidopaminergic effects of medication. Thus, it is important to capture the association between striatal dopamine D2 receptor occupancy (D2-RO) and global subjective well-being. We examined this association using data from our multicenter, randomized, double-blind Neuroleptic Strategy Study (NeSSy). Methods An innovative double randomization process was used for allocation of patients to the specific treatment groups. Plasma drug concentrations were measured after 6 and 24 weeks of treatment to obtain the estimated D2-RO (eD2-RO) relative to literature val…
Automated Determination of Ziprasidone by HPLC With Column Switching and Spectrophotometric Detection
2005
An isocratic high-performance liquid chromatography (HPLC) method with column switching and ultraviolet (UV) detection is described for quantitative analysis of the new antipsychotic drug ziprasidone. After centrifugation of serum or plasma samples and addition of fluperlapine as internal standard, the samples were injected into the HPLC system. On-line sample clean-up was conducted on a column (10 x 4.0 mm ID) filled with silica C8 material (20-microm particle size) using 8% (vol/vol) acetonitrile in deionized water as eluent. Ziprasidone was eluted and separated on ODS Hypersil C18 material (5 microm; column size 250 x 4.6 mm ID) using acetonitrile-water-tetramethylethylendiamine (50:49.6…
Tratamiento psicofarmacológico del trastorno bipolar en América Latina
2011
Objective: This study assessed the treatment preferences among Latin-American psychiatrists for their bipolar disorder patients and if these preferences reflect the current guidelines. Methods: We designed a survey comprised of fourteen questions. All the questions were aimed at the treatment of bipolar I patients only. We distributed the survey by hand or e-mail to psychiatrists in eight different countries: Argentina, Brasil, Colombia, Costa Rica, Ecuador, México, Perú and Venezuela. Between May 2008 and June 2009, we were able to gather 1143 surveys. Results: As the initial choice of treatment for a bipolar patient who debuts with mania, 61.3% choose a combination of an atypical antipsyc…
Simultaneous determination of olanzapine, clozapine and demethylated metabolites in serum by on-line column-switching high-performance liquid chromat…
2001
An automated method for simultaneous routine quantification of the antipsychotic drugs clozapine, olanzapine and their demethylated metabolites is described. The method included adsorption on a cyanopropyl (CPS) coated clean-up column (10 microm; 10 x 2.0 mm I.D.), washing off interfering serum constituents to waste, and separation on C18 ODS Hypersil reversed phase material (5 microm; 250 x 4.6 mm I.D.) using acetonitrile-water-tetramethylethylenediamine (37:62.6:0.4, v/v/v) adjusted to pH 6.5 with concentrated acetic acid. UV-detection was performed at 254 nm. The limit of quantification was 10-20 ng/ml. Relative day to day standard variations ranged between 4.5 and 13.5%. The method is s…
Automated analysis of quetiapine and other antipsychotic drugs in human blood by high performance-liquid chromatography with column-switching and spe…
2004
Abstract An automated HPLC method with column switching is described for the determination of quetiapine, clozapine, perazine, olanzapine and metabolites in blood serum. After clean-up on silica C8 material (20 μm particle size) drugs were separated on ODS Hypersil C18 material (5 μm; column size 250 mm × 4.6 mm i.d.) within 25 min and quantified by ultraviolet (UV) detection at 254 nm. The limit of quantification ranged between 10 and 50 ng/ml. At therapeutic concentrations of the drugs, the inter-assay reproducibility was below 10%. Analyses of drug concentrations in serum of 75–295 patients treated with therapeutic doses of the antipsychotic drugs revealed mean ± S.D. steady state concen…
Comparing Long-Acting Antipsychotic Discontinuation Rates Under Ordinary Clinical Circumstances: A Survival Analysis from an Observational, Pragmatic…
2021
Background Recent guidelines suggested a wider use of long-acting injectable antipsychotics (LAI) than previously, but naturalistic data on the consequences of LAI use in terms of discontinuation rates and associated factors are still sparse, making it hard for clinicians to be informed on plausible treatment courses. Objective Our objective was to assess, under real-world clinical circumstances, LAI discontinuation rates over a period of 12 months after a first prescription, reasons for discontinuation, and associated factors. Methods The STAR Network ‘Depot Study’ was a naturalistic, multicentre, observational prospective study that enrolled subjects initiating a LAI without restrictions …