How often must clients receiving clozapine get white blood cell counts drawn?

Patiens that receive clozapine (Clozaril) must get white blood cell counts drawn every 3 months.

Clozapin is an antipsyhotic medication used for the treatment of schizophrenia. Clozapine is very effective but it is associated with a relatively high risk of low white blood cells. As a consequence immunity is suppressed and may result in death.