Benign ethnic neutropenia (BEN) is an important issue in clozapine-treatment. Clozapine is effective in treatment-resistant schizophrenia. Agranulocytosis is a severe adverse effect of clozapine that limits its more widespread use. Total white cell and/or neutrophil counts indicate agranulocytosis. Patients with low counts cannot start or have to discontinue clozapine-treatment. Agranulocytosis due to clozapine occurs in about 1% of patients taking clozapine, neutropenia in about 3% (Rajagopal,2005).

Among many ethnic groups, a significant proportion of people have BEN. Definition of BEN: “When neutropenia, defined by normative data in white populations, occurs in individuals of other ethnic groups who are otherwise healthy and who do not have repeated or severe infections, the condition may be referred to as benign ethnic neutropenia” (Haddy, 1999: p15).

Prevalence of neutropenia and leukopenia according to Shoenfeld, 1988 among Ethiopian Jews (Falashas) (who migrated to Israel):
Leukopenia 55%
Neutropenia 39%