Health Canada advises that manufacturer sales of thioridazine, an anti-psychotic medication used to treat schizophrenia, will be stopped by September 30, 2005.
Thioridazine will continue to be dispensed by pharmacies for a transition period after that date to allow patients sufficient time to consult their health care providers and switch to an alternate medication.
Health Canada has taken this action because manufacturers have failed to provide convincing safety information, requested by the Department, that demonstrates that the drug is safe to use. Questions of safety arose from ongoing concerns about use of the medication and rare occurrences of heart rhythm changes that could be life-threatening.
Health Canada is advising patients who use thioridazine not to stop taking their medication and to consult their physicians or health care providers as soon as possible in order to be switched to an alternate medication or medications.
In June 2005, Health Canada, which had been monitoring the safety of the drug, requested that manufacturers of generic thioridazine provide evidence that the benefits of using the drug outweigh the risks, especially given that potentially safer anti-psychotic medications are available.
Information submitted to Health Canada to date has failed to demonstrate that the benefits outweigh the risks. Health Canada has received reports of three deaths between 2000 and 2005 possibly related to thioridazine, with the most recent death occurring in February 2005.
Health Canada estimates there will be sufficient supplies in pharmacies to allow patients time to change to another product. Should pharmacy supplies be inadequate or if patients are unable to make a safe transition to marketed alternatives, prescribers should contact the Special Access Programme at Health Canada to request temporary access to the drug for individual patients. In most cases, alternative therapies are available to treat schizophrenia. Availability of thioridazine through the Special Access Programme may be an option for patients who cannot be adequately managed on alternative therapies.
Thioridazine has been used in Canada for the treatment of schizophrenia since 1959. The original brand name of thioridazine was Mellaril. In July 2000, Novartis Pharma Canada Inc., the manufacturer of Mellaril, distributed a letter to Canadian health care professionals that discussed safety concerns of potentially life-threatening changes in heart rhythm. Novartis withdrew the drug from the Canadian market in July 2001. The withdrawal was due to issues with changes to labelling and prescribing information that had been requested by Health Canada.
Novartis subsequently advised Health Canada that the company would voluntarily discontinue Mellaril worldwide by June 30, 2005 due to safety concerns. The move by Health Canada to stop the sale of thioridazine follows the Novartis decision.
Since 2001, generic manufacturers have continued to produce thioridazine for the Canadian market. Brand names currently available on the Canadian market include Thioridazine and Apo-thioridazine.