[Frequent cases of agranulocytosis due to clozapin (leponex) in eastern Switzerland].

Two personally observed cases of severe agranulocytosis within 3 months, one of them fatal, could be attributed to the new dibenzodiazepine derivative Clozapine (Leponex). Clozapine, a very effective neuroleptic for the treatment of acute and chronic schizophrenia, has been found before to induce agranulocytosis of the metabolic type, as phenothiazines are known to do. An inquiry in al Swiss medical departments and mental hospitals revealed a total of 20 cases of Clozapine induced agranulocytosis in some 50% of institutions responding. 9 of these were observed in Eastern Switzerland. This time-space clustering recalls the "finnish epidemic" of 1975 in Southern Finland. Possible explanations for this phenomenon are discussed. Calculations of the incidence suggest a higher rate of agranulocytosis induced by Clozapine than has been assumed for the phenothiazines. Clozapine should therefore be restricted to schizophrenic patients and initially (6 weeks) be given only on a stationary basis under regular blood controls.