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Health Canada Releases Important Information on the Dispensation of CLOZAPINE Products in Canada – Notice to Hospitals

Starting date:
June 23, 2004
Posting date:
June 23, 2004
Type of communication:
Notice to Hospitals
Source of recall:
Health Canada
Important Safety Information
Identification number:

Notice about Health Canada advisories

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Notice to Hospitals - Health Canada releases important information on the dispensation of CLOZAPINE products in Canada

June 23, 2004

To: Hospital Chief of Medical Staff

Please distribute to the relevant Departments of Pharmacy and Psychiatry and other involved professional staff and post this NOTICE in your institution.

Subject: Monitoring of patients taking clozapine

The Marketed Health Products Directorate (MHPD) and the Therapeutic Products Directorate (TPD) would like to draw your attention to important upcoming revisions to the Product Monograph of all clozapine products marketed in Canada. These revisions will strengthen the labeling and address ongoing issues around patient consent for the sharing of information between registries, considered important due to the well-known risk of agranulocytosis associated with clozapine use.

Revisions to clozapine Product Monographs will emphasize the following:

  1. the switching of a patient from one brand of clozapine to another must not be done by a pharmacist unless he/she obtains a new, registry-specific patient registration form filled out by the prescribing physician.
  2. the physician has to inform his/her patient about the potential sharing of information between clozapine registries and document if there is consent from the patient to allow it, in order to ensure the safe use and continuous monitoring of patients taking clozapine.
  3. the responsibility of physicians concerning the sending of the mandatory laboratory results to the appropriate registry will be limited to informing the laboratory where the patient's haematological results have to be sent.
  4. weekly monitoring of neutrophils and white cells counts for four weeks at the end of the treatment is necessary only in case of cessation of all clozapine treatment.

Patients on clozapine and their treating physicians and dispensing pharmacists have to be enrolled in registries, which are currently specific to each market authorization holder. Patients must undergo regular haematological tests to monitor their total white blood-cell and absolute neutrophil counts. Between 1991 and 2003, clozapine was distributed by a single manufacturer, and patients were monitored by this manufacturer's specific registry. The introduction of generic clozapine in the last year has led to the establishment of other registries.

Health Canada is taking the following steps to ensure the safe use and continuous monitoring of patients taking clozapine in Canada:

  • inclusion of a statement in the registry-specific Patient Registration Form signed by the treating physician (see attachment 1 in the Health Professional Letter), certifying that the patient has been informed of the necessary sharing of information between clozapine registries to enable continuous monitoring and safe use of the medication. As a preventive measure and to avoid any confusion, physicians may also ask patients already on clozapine to fill out the updated Patient Registration Form.
  • A "Questions and Answers" patient information leaflet, prepared in collaboration with the Schizophrenia Society of Canada, is also provided (see attachment 2 in the Health Professional Letter), to help physicians to document the actual consent from the patient on information exchange between registries.
  • Appropriate revision of clozapine Product Monographs to reflect the above.

The implementation of these steps will permit the achievement of a more efficient network of independent registries, and therefore improve the continuity of care of patients treated with clozapine.

The identification, characterization, and management of marketed health product-related adverse reactions are dependent on the active participation of health care professionals in adverse reaction reporting programmes. Any occurrences of serious and/or unexpected adverse reactions in patients receiving clozapine should be reported to Health Canada at the following address:

Canadian Adverse Drug Reaction Monitoring Program (CADRMP)
Marketed Health Products Directorate
Address Locator: 0701C
OTTAWA, Ontario, K1A 0K9
Tel: (613) 957-0337 or Fax: (613) 957-0335
To report an Adverse Reaction, consumers and health professionals may call toll free:
Tel: 866 234-2345
Fax: 866 678-6789

For other inquiries: please refer to contact information.

The AR Reporting Form and the AR Guidelines can be found on the Health Canada web site or in The Canadian Compendium of Pharmaceuticals and Specialties.

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