Introduction : clozapine is the first effective antipsychotic drug with the least extra pyramidal side effects and more agranulocytosis than other standard neuroleptics. Granolocytopenia or agranulocytosis occurs in 1 to 2 percent of all patients treated with clozapine. agranulocytosis due to clozapine is a fatal disorder that requires immediate clinical intervention.

  Method : this paper reports agranulocytosis after clozapine treatment in a 52 years old women with chronic schizophrenia. Conclusion: since agranulocytosis after clozapine treatment is rare and its side effects in psychotic patients are very few, it seems that clozapine with regular blood cell count is an effective drug in the treatment of refractory schizophrenia, patients with tradive dyskinesia and those experiencing severe extra pyramidal side effects.