There are no standards indicating critical values for
serum clozapine/norclozapine levels. A review of the
literature indicates that only 2-4 anecdotal case reports
identified seizures at clozapine levels > 4000 nmol/L.
Although a relationship between dose at 500 - 600 mg/d and
seizures has been substantiated, there is no clear
relationship between doses and levels, and no evidence that
risk of seizures increases once dose has exceeded 500 -
600 mg/d. For help with interpretation of serum clozapine/
norclozapine levels or reference (s) to this information
please consult the Clinical Chemist at Dynacare
Laboratories.
Reference ranges are valid only for appropriate collection
times: pre-dose (trough), just prior to the next scheduled
dose, or post dose at a time >75% of the dosing interval.

Nanomole/Litre