Transient neutropenia induced by clozapine.
Blood dyscrasias are frequently reported to be induced by the atypical antipsychotic clozapine. Next to agranulocytosis, a potentially lethal form of these side effects, hematologic disturbances include leucocytosis, eosinophilia, and neutropenia. Neutropenia is of considerable clinical relevance because it can be a sign of incipient agranulocytosis. In an analysis of our clozapine drug monitoring program, we have analyzed the data from 68 patients receiving clozapine for the first time. Neutrophil granulocytes dropped to 290 and 660/mm3 in 2 patients, both recovered after the discontinuation of clozapine. Another patient with a granulocyte count of 1800/mm3 was stopped because regular white blood cell monitoring was not possible. Eight additional patients demonstrated a transient decrease of granulocytes during ongoing clozapine administration. This amounts to a cumulative incidence of transient neutropenia of 22 percent (95% confidence interval 7.5%-36.5%).
Hummer
M
M
Department of Psychiatry, Innsbruck University Clinics, Austria.
Kurz
M
M
Barnas
C
C
Fleischhacker
W W
WW
D000328:Adult; D003024:Clozapine / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D009503:Neutropenia / Q000139:chemically induced*
D003024:Clozapine