Clozapine for refractory schizophrenia: an open study of 14 patients treated up to 2 years.

Clozapine is a novel antipsychotic agent that selectively blocks mesolimbic--rather than nigrostriatal--dopamine receptors, causes fewer extrapyramidal symptoms than do other neuroleptics, and has superior antipsychotic efficacy in some patients. However, clozapine also causes agranulocytosis more frequently than do other neuroleptics. The evidence documenting the superior benefits obtained with clozapine has primarily involved short-term (4-6 weeks) trials, and the systematic evaluation of long-term clozapine use has been limited. In this study, 14 patients with refractory chronic schizophrenia were treated openly with clozapine up to 2 years; 8 did substantially better when given clozapine than they had when given other neuroleptics. That finding suggests that clozapine may provide a useful addition to the therapeutic armamentarium for the long-term treatment of schizophrenia, despite the increased risks and the need for frequent blood tests.