OBJECTIVE To study rates of relapse in remitted patients with first episode psychosis who either continued or discontinued antipsychotic drugs after at least one year of maintenance treatment. DESIGN 12 month randomised, double blind, placebo controlled trial. SETTING Early psychosis outpatient clinics in Hong Kong. PARTICIPANTS 178 patients with first episode psychosis who had received a...

OBJECTIVE Clozapine, the prototype of atypical antipsychotics, remains unique in its efficacy in the treatment of refractory schizophrenia. Its affinity for dopamine D(4) receptors, serotonin 5-HT(2A) receptor antagonism, effects on the noradrenergic system, and its relatively moderate occupancy of D(2) receptors are unlikely to be the critical mechanism underlying its efficacy. In an attempt t...

BACKGROUND How long an antipsychotic is effective in maintaining response is important in choosing the correct treatment for people with schizophrenia. This post-hoc analysis describes maintenance of response over 24 or 28 weeks in people treated for schizophrenia with olanzapine, risperidone, quetiapine, ziprasidone, or aripiprazole. METHODS This was a post-hoc analysis using data from 5 dou...

OBJECTIVE The aim of this analysis was to compare the effects of 2 atypical antipsychotic agents, lurasidone (80 mg/d or 160 mg/d) and quetiapine XR (600 mg/d), on daytime alertness, and to evaluate the effects of daytime sleepiness on treatment outcomes in patients with an acute exacerbation of schizophrenia. METHODS Patients who met Diagnostic and Statistical Manual of Mental Disorders, 4th...

BACKGROUND Atypical antipsychotic drugs may have low propensity to induce extrapyramidal side effects in delirious patients. This study aimed to compare the efficacy and tolerability between quetiapine and haloperidol in controlling delirious behavior. METHODS A 7-day prospective, double-blind, randomized controlled trial was conducted from June 2009 to April 2011 in medically ill patients wi...

BACKGROUND The dopaminergic system is implicated in many mental processes and neuropsychiatric disorders. Pharmacologically, drugs with dopamine receptor antagonistic and agonistic effects are used, but their effects on functional brain metabolism are not well known. METHODS In this randomized crossover, placebo-controlled, and rater-blinded study, 25 healthy adults received an acute dose pla...

BACKGROUND Cognitive deficits are recognized as a critical determinant of functional outcomes in schizophrenia; and second generation antipsychotic drugs have been touted for their potential to enhance cognitive functioning and community tenure. OBJECTIVES The study examined the relative merits of olanzapine and quetiapine in improving cognitive deficits and enhancing psychosocial functioning...

PURPOSE To evaluate and compare the therapeutic efficacy of quetiapine in bipolar I and II depression patients in the clinical setting. PATIENTS AND METHODS This was an 8-week, multicenter, open-label, observational study for bipolar depression. The dosage of quetiapine was flexible, and concomitant medications were permitted on clinician's judgments. A total of 1097 patients were enrolled, a...

The aim of this post-hoc analysis was to determine whether early symptom improvement with extended release quetiapine (quetiapine XR) may predict treatment outcome in patients with major depressive disorder. Data were from 6, double-blind, placebo-controlled studies of quetiapine XR (2 fixed-dose and 2 flexible-dose monotherapy and 2 adjunct studies) in adult patients with major depressive diso...

Comorbid substance use in schizophrenic patients is common, and substance dependence is a predictive factor for psychosis. The present study was designed to investigate the effects of risperidone, quetiapine and ziprasidone, atypical antipsychotic drugs, on ethanol withdrawal syndrome (EWS) in rats. Adult male Wistar rats were used in the study. Ethanol (7.2%, v/v) was given to rats via a liqui...