J. Alfaro et al., A CASE OF CLOZAPINE-INDUCED NEUTROPENIA A ND AGRANULOCYTOSIS - THE IMPORTANCE OF ITS EARLY DETECTION THROUGH A DRUG SURVEILLANCE PROGRAM, Revista Medica de Chile, 122(6), 1994, pp. 694-698
Clozapine is an atypical antipsychotic drug with a very low incidence
of extrapyramidal effects, used in the treatment of schizophrenic pati
ents refractory or intolerant to classical neuroleptics. Its use is li
mited due to the potential risk of producing agranulocytosis in 1 to 2
% of patients. Despite the severity of this complication, the Federal
Drug Administration allowed its use as long as its prescription is ass
ociated to a drug surveillance program that controls regularly the whi
te cell count of patients using the drug. Three hundred three patients
(210 male) have been admitted to a clozapine drug surveillance progra
m. Two patients had a transitory leukopenia with less than 2000 leukoc
ytes/ml and less than 1000 neutrophyls/ml, that reverted after discont
inuing the drug. One patient, whose case is described, had a severe ag
ranulocytosis with less than 500 neutrophyls/ml that required hospital
admission.