Clozapine treatment in Denmark: concomitant psychotropic medication and hematologic monitoring in a system with liberal usage practices.

BACKGROUND

Clozapine has been utilized in Denmark since the early 1970s. This study examines doses, concomitant psychotropics, and leukocyte counts.

METHOD

All psychiatric hospitals in Denmark were asked for copies of all their clozapine monitoring forms, which were then personally reviewed by the authors.

RESULTS

Forms from 656 patients were collected from 32 hospitals. The male/female ratio was 2/1; the median age, 38 years (range, 18-80). Thirty-five percent received concomitant antipsychotics, 28% benzodiazepines, 19% anticholinergics, 11% antidepressants, 8% antiepileptics, (carbamazepine, valproate, and phenobarbital), and 2% lithium. While there were no gender differences with respect to concurrent psychotropics, women received lower doses of clozapine than men (median dose, women 300 mg/day and men 400 mg/day, p < .02). Ten percent had had a neutrophil count < 2000/microL (3.2% < 1500/microL). Five percent had repeated neutrophil counts < 2000/microL (1.5% < 1500/microL). There were two cases of agranulocytosis; both patients fully recovered upon withdrawal of clozapine. Clozapine was discontinued because of hematologic abnormalities in only five other cases (0.8%).

CONCLUSION

While use of concomitant psychotropics during clozapine treatment should be limited because of an increased risk of complications, a totally restrictive policy might deprive certain patients of the benefits of clozapine treatment. There appears to be a benign form of granulocytopenia that does not always necessitate discontinuation, provided there is close follow-up.