title: Successful challenge with clozapine in a history of eosinophilia.
abstract: Eosinophilia has been encountered from 0.2 to 61.7% in clozapine-treated patients, mostly with a transient course and spontaneous remission. There have been few reports, however, which have investigated a challenge with clozapine in patients previously showing eosinophilia. Two case reports are presented: the first with clozapine challenge after eosinophilia, the second under clozapine treatment and no previous haematological side effects. The challenge case showed eosinophilia with 1.2 10(9)/l (z = 1.79, p = 0.04) being followed by normalization despite clozapine continuation, whereas the maximum value reached 2.1 10(9)/l in the single episode case, with consecutive normalization and uninterrupted treatment. Eosinophilia caused by clozapine was observed in challenge, preceded by a faster neutrophil production and consecutive decrease (z = 2.27, p = 0.01). A challenge with clozapine was feasible and showed no clinical symptoms of eosinophilia.
authors.affiliation: Psychiatric Services of the University of Berne, Switzerland.
authors.forename: D
authors.initials: D
authors.lastname: Schuepbach
authors.forename: M C
authors.initials: MC
authors.lastname: Merlo
authors.forename: L
authors.initials: L
authors.lastname: Kaeser
authors.forename: H D
authors.initials: HD
authors.lastname: Brenner
mesh_terms: D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D003024:Clozapine / Q000008:administration & dosage / Q000009:adverse effects*; D003866:Depressive Disorder / Q000188:drug therapy; D004802:Eosinophilia / Q000139:chemically induced*; D006801:Humans; D008297:Male; D012559:Schizophrenia / Q000188:drug therapy; D016896:Treatment Outcome