Also Known As: Clozapine, Clozaril, Azaleptin, Leponex, Fazaclo, Froidir, Denzapine
Clozapine (sold as Clozaril, Azaleptin, Leponex, Fazaclo, Froidir; Denzapine, Zaponex in the UK; Klozapol in Poland, Clopine in Australia and New Zealand) is an antipsychotic medication used in the treatment of schizophrenia, and is also used off-label in the treatment of bipolar disorder. Wyatt. R and Chew. R (2005) tells us there are three pharmaceutical companies that market this drug at present: Novartis Pharmaceuticals (manufacturer), Mylan Laboratories and Ivax Pharmaceuticals (market generic clozapine). The first of the atypical antipsychotics to be developed, it was first introduced in Europe in 1971, but was voluntarily withdrawn by the manufacturer in 1975 after it was shown to cause agranulocytosis, a condition involving a dangerous decrease in the number of white blood cells, that led to death in some patients. In 1989, after studies demonstrated that it was more effective than any other antipsychotic for treating schizophrenia, the U.S. Food and Drug Administration (FDA) approved clozapine's use but only for treatment-resistant schizophrenia. The FDA requires blood testing for patients taking clozapine. The FDA also requires clozapine to carry five black box warnings for agranulocytosis, seizures, myocarditis, for "other adverse cardiovascular and respiratory effects", and for "increased mortality in elderly patients with dementia-related psychosis." In 2002 the FDA approved clozapine for reducing the risk of suicidal behavior for patients with schizophrenia.
Clozapine is usually used as a last resort in patients that have not responded to other anti-psychotic treatments due to its danger of causing agranulocytosis as well as the costs of having to have blood tests continually during treatment. It is, however, one of the very effective anti-psychotic treatment choices. Patients are monitored weekly for the first six months. If there are no low counts the patient can be monitored every two weeks for an additional six months. Afterwards, the patient may qualify for every four week monitoring. Clozapine has numerous severe side effects including agranulocytosis, bowel infarction, seizures, myocarditis, and diabetes. Additionally, it also often causes less serious side effects such as sialorrhea and weight gain.