Sir: Approximately 70% of clozapine metabolism is explained by the cytochrome P450 1A2 (CYP1A2). The CYP1A2 can be inhibited by respiratory infections. Decreased theophylline (a CYP1A2 substrate) clearance during upper respiratory infections has been described in asthmatic children and in adults with chronic bronchitis. Cytokines released during infection decrease CYP1A2 activity and synthesis....

Sir: Approximately 70% of clozapine metabolism is explained by the cytochrome P450 1A2 (CYP1A2). The CYP1A2 can be inhibited by respiratory infections. Decreased theophylline (a CYP1A2 substrate) clearance during upper respiratory infections has been described in asthmatic children and in adults with chronic bronchitis. Cytokines released during infection decrease CYP1A2 activity and synthesis....

Clozapine, a second-generation antipsychotic, is the treatment of choice in refractory schizophrenia because of its proven efficacy over typical antipsychotics as well as other atypical antipsychotics (1). However, a major drawback to clozapine therapy is the increased risk of neutropenia and agranulocytosis (2). In patients who develop either of these serious side effects, clozapine is immedia...

BACKGROUND Although clozapine is the 'gold standard' for treatment-refractory schizophrenia, meta-analyses of clozapine for this condition are lacking. AIMS We conducted a systematic review and meta-analysis of clozapine treatment for people with treatment-refractory schizophrenia. METHOD We searched the Cochrane Schizophrenia Group's trial register, PubMed and EMBASE and hand-searched key ...

Clozapine, an atypical antipsychotic, has proved to be superior to other antipsychotics in treating patients with refractory schizophrenia. An increased plasma clozapine level above the therapeutic window may be associated with serious adverse events including paralytic ileus. Clozapine toxicity may occur in association with infection or after drug overdose. In a medical emergency situation, di...

BACKGROUND Clozapine is the only antipsychotic drug licensed for treatment-resistant schizophrenia but its use is often delayed. Since previous studies, national guidelines on the use of clozapine and other antipsychotics have been disseminated to clinicians. AIMS To determine the theoretical delay to clozapine initiation and to quantify the prior use of antipsychotic polypharmacy and high-do...

Sir: Approximately 70% of clozapine metabolism is explained by the cytochrome P450 1A2 (CYP1A2). The CYP1A2 can be inhibited by respiratory infections. Decreased theophylline (a CYP1A2 substrate) clearance during upper respiratory infections has been described in asthmatic children and in adults with chronic bronchitis. Cytokines released during infection decrease CYP1A2 activity and synthesis....

Clozapine is an antipsychotic drug which is unusual in that it has no dopamine receptor-blocking activity. Previous studies gave conflicting results whether administration of clozapine induces hyperprolactinemia. In the present study it was shown that a wide concentration range of clozapine does not interfere with dopamine-mediated inhibition of prolactin (PRL) secretion by normal cultured rat ...

OBJECTIVE Clozapine is one of the most commonly used antipsychotic drugs in China. To date, few studies have investigated the patterns the prescription of clozapine nationwide. The present study examined these patterns in China in 2006 and identified the demographic and clinical characteristics associated with the use of clozapine. METHODS Using a standardized protocol and data collection pro...